Parents with cancer often have to worry about their children, along with treatments and medical bills.

On the first day of spring 2007, Francesca Giessmann, 43, a marketing executive and holistic health coach from Kirkland, Washington, was rushed to the emergency room with severe stomach pain.

After running numerous tests, doctors gave her the diagnosis of stage 3 non-Hodgkin lymphoma.

Shocked and saddened by the news of her cancer, Giessmann’s thoughts quickly turned to her son, Leo, who’d turned 3 years old the month prior.

“Leo was very young and could not fully understand what was going on,” Giessmann said. “Our pediatrician suggested we try to keep everything normal. I spent a great deal of time in bed. Leo related to my disease based on my port. He thought I had a boo-boo.”

Giessmann, who has had an enormous amount of health complications and side effects since her cancer treatment, said that when Leo turned 6 years old, he told her he was afraid his parents were going to die and he would be left alone.

Leo is now, as Geissmann describes him, an articulate preteen who’s come to terms with his mom’s cancer.

“I’ve often heard him say how his mom had cancer and ‘she beat it,’” Giessmann said. “It is equal parts heartbreaking and heartwarming. He is very protective of me. My cancer has made him grow up a bit too fast. He’s more sensitive and I think he has an understanding of the fragility of life.“

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Cancer affects the entire family.

But the emotional and psychosocial impact on a child whose parent has cancer often goes unnoticed and unattended.

The American Cancer Society estimates that about 1.7 million adults will be diagnosed with cancer in 2016. That leaves 749,000 children under the age of 18 years old who will be affected this year.

It is estimated that nearly 3 million children under the age of 18 are currently living with the challenge of coping with a parent who has cancer.

For Giessmann and so many other mothers and fathers, cancer is an education not only in survival, but also in parenting.

How do you keep your children happy and make them feel safe when you are sick, and scared yourself and fighting a potentially fatal disease?

You just have be as honest as you can with your children, and try to stay strong and positive, “even during the darkest times,” said Eric Wassyng, 63, a technical writer from a northern Virginia suburb. His 26-year-old daughter was 14 when he was diagnosed with small lymphocytic lymphoma in April 2004.

“I was open about everything I went through,” Wassyng said. “My daughter is naturally curious and actually did her own research and came up with practically the correct diagnosis. I let her know that my life was definitely threatened, but I was getting the best care possible and was determined to fight it. Obviously, if she were a younger child, I may have withheld some information.”

Wassyng, who’s been in remission since he received an autologous stem cell transplant in 2005, said his daughter just wanted to be reassured that she would have a dad for a long time.

“Three years after my diagnosis, my wife also had cancer,” he said. “She is also in complete remission now. Having experienced one parent with cancer definitely helped her get through another one. Our small family has come to terms with our mortality.”

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The many parents interviewed for this story who have been diagnosed with cancer agreed that it is sometimes tough to find the right words when speaking to their children about cancer and the child’s anger, sadness, confusion, and fear.

Oncologists and others on a cancer patient’s medical team are typically focused on the treatment of the patient. But a parent’s first concern is for their children — an area that parents say many cancer hospitals are still not adequately addressing.

Teresa Thorson, 48, is a school bus driver from Wisconsin who shows horses and is the married mother of two children. When she began treatment for her uterine cancer earlier this year, she didn’t want to know what stage her cancer was or what her chances of survival were.

“I just knew I had to fight for my kids,” said Thorson, who turned to Children’s Lives Include Moments of Bravery (CLIMB).

The program is the nation’s first research-based psychosocial intervention program for children who have a parent with cancer.

CLIMB helps kids deal with their feelings of sadness, anxiety, fear, and anger, and stimulates improved communication between the children and their parents.

CLIMB, which was operating at the hospital where Thorson received her treatment, is part of the Children’s Treehouse Foundation, a Colorado-based, global nonprofit organization. Its mission is to assist children who have a parent, grandparent, or guardian with cancer.

Thorson said her son Tylor, 13, and daughter Cloe, 9, started the program in April just a few days after their grandmother died from cancer and just as Thorson began her treatment.

“Tylor is quiet. He’s not a big talker. Sometimes it’s like pulling teeth,” Thorson said. “The CLIMB program got through to him, he came home happier afterward. I honestly think it did wonders for both of them. It also helped when they discovered that other kids in the CLIMB group were going through the same thing. There was another family, two other kids, not a huge group, but they all got along, they clicked.”

When Thorson started to lose her hair from the chemo, she cut her son’s hair and then asked him if he wanted to cut her hair.

“He had to wrap his head around the fact that he was going to shave my head,” she said with a tear-filled laugh. “My daughter helped him cut my hair. Tylor did the top of my head and Cloe did the back.”

Thorson, who is still in the midst of her chemotherapy, said that as a parent with cancer you feel “helpless” sometimes.

“I’ve muddled through, getting the kids off to school,” she said. “I’d just fake it for a little bit then go back to bed. But there are nights when I don’t feel good and I tell them, ‘I can’t put you guys to bed, you guys have to put mom to bed tonight.’”

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Barb Williams, 62, who works with special needs children in Caldwell, Idaho, was diagnosed with breast cancer a year ago.

She was concerned about how her three grandkids, whom she is close with, would take the news.

The children — Rosalina Zamora, 12, Analisa Zamora, 10, and Victoria Zamora, 9, — had recently suffered the loss of their father, a veteran of the wars in Iraq and Afghanistan, who died in a tragic car accident between deployments.

All three children took part in the CLIMB program, along with their mother, Ashley Zamora, and her boyfriend.

”It helped the kids a lot, especially with their fear and with the unknown,” Williams said.

Ashley Zamora said her three daughters are very close to their grandmother, and they’d already lost their father and a beloved aunt who died of cancer.

“My daughters all reacted to their father’s death, the death of their great aunt, and to their grandmother’s cancer in different ways,” Zamora explained. “My youngest daughter was afraid to go near her grandmother. She was afraid it might be contagious. And my oldest daughter just shut down completely. CLIMB helped all of them cope.”

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Losing a father to a car accident, then a great aunt to cancer, and then seeing your grandmother go through cancer treatment would seem like too much for any child to handle.

But Victoria Zamora, 9, told Healthline just how the CLIMB program has helped her get through it.

“CLIMB helped me understand what my grandma was going through, what would happen to her, and what cancer was,” she said. “For example, we made an anger cube and on the sides we wrote what we could do when you’re mad. My Aunt Christine had lung cancer and died. When I found out that my grandma had cancer my first thought was, ‘Oh no.’ I was scared that the same thing would happen to her. I felt really sad, like it wasn’t fair, why did it happen to us. I was sad and nervous. I felt scared my grandma was going to die like my daddy and my aunt.”

Victoria said she learned through the CLIMB program that, “If you felt like you wanted to cry, then just cry, because if you held it in it will build up inside you and one day you might just burst because of everything you held in.”

Victoria said that even before her grandmother lost her hair, “I was scared of her because she had cancer. I didn’t know what was happening to her, but CLIMB helped me understand what cancer was. I learned there was a lot of cancer and what kind my grandma had. She had breast cancer. We went and saw what machines they used like for radiation and chemo and that it was going to help my grandma to get better.”

Victoria concluded, “I’m happy my grandma survived and that her hair is growing back and that she is doing great. I love my grandma so much.”

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Peter van Dernoot, a former public relations executive, founded the Children’s Treehouse Foundation in 2001 after his wife was diagnosed with lung cancer in her 40s. He said the foundation’s mission is ensuring that every child whose parent is diagnosed with cancer is given the early tools and emotional support to cope.

“Even now, 36 years after we discussed with our two young children that their mom had cancer, I still get emotionally chocked up when asked to recount my experience,” said van Dernoot, who remains chairman of the foundation’s board of directors.

While cancer centers are providing ever improving cancer treatment to their patients, he added, they are woefully negligent in providing emotional strategies for the rest of the family, especially the children.

“This is regrettable since studies show that when the stress the children have has diminished, the stress of the cancer-parent is reduced, and her/his immune system responds better,” van Dernoot noted. “It’s a win-win situation. It’s unthinkable that parents should be expected to know how to talk to their children about cancer. They need professional guidance to do this. It is our fervent hope that more cancer centers will adopt psychosocial intervention programs similar to CLIMB.”

Van Dernoot noted that the CLIMB program is now available in 77 cancer centers in the United States, including such prominent hospitals as the University of Texas MD Anderson Cancer Center, the University of Colorado Cancer Center, Memorial Sloan Kettering Cancer Center in New York, and Cancer Treatment Centers of America in Philadelphia.

Last year, the program, which is in 18 centers in seven other countries, served an estimated 1,560 children with its CLIMB program, representing more than 600 families.

A recent study of CLIMB by the Omni Institute reported the first quantitative analysis of the program’s effects. The study evaluated the psychobehavioral benefits of the CLIMB intervention in 45 children ages 6 to 11.

Pallavi D. Visvanathan, Ph.D. at OMNI Institute, and Amanda J. Shallcross, N.D., M.P.H. at New York University School of Medicine, led the study.

It showed that children who enrolled in the program had statistically significant improvements coping with such issues as parent-child communication, emotional symptoms, loneliness, peer problems, and positive social behavior.

Denis Murray, the Children’s Treehouse Foundation’s executive director, told Healthline, “It’s striking to me how many parents tell us that when they were diagnosed with cancer, their first concern was their children. Not their treatment, not themselves.”

Murray, a melanoma cancer survivor himself, whose father died of pancreatic cancer when he was 15 years old, said that a cancer treatment plan is not comprehensive until it includes concern for the patient’s children.

“The children will know something is wrong,” Murray said. “When they are brought into the challenge of facing a parent’s cancer, they will surprise you with their strength, their insight, and the support they can provide, even though they’re ‘just kids.’ They’ll surprise you with their bravery.”

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Cathy Morris, 45, is married and has three boys — son Dylan, and stepsons Nick and David.

When she learned that she had cancer, Morris wasn’t sure how she was going to share this information with Dylan, who has autism and Tourette’s syndrome.

Morris said that at first she didn’t believe Dylan understood.

But as he’s gotten older, “He asks questions and I answer them as honestly and truthfully as possible. Sometimes it’s hard to know what he’s feeling. Occasionally he’ll tell me he’s sad and that he doesn’t want me to die. I just remind him I have no plans on leaving.”

Her role as a person with cancer and parent of a child with special needs has been no easy task. Morris said, “I believe that no matter what your journey is when dealing with cancer, there are just some things you can’t lose: your sense of humor, the ability to have fun, showing love to those that matter the most, being able to ask for help, and most importantly helping yourself.”

Each of the parents interviewed for this story echoed the sentiment that while their kids do struggle, they also often triumph.

The parents unanimously agreed that children are resilient and are stronger, more courageous, and more aware of what is going on than adults sometimes think or expect.

When asked what advice he would give to other kids who have a mom, dad, or grandparent with cancer, Leo Giessmann, the 12-year-old son of survivor Francesca Giessmann, said, “I would say to stay calm. Always support them. And go to the hospital to see them, even if it is a pain. Never lose hope. There is always a chance.”

Editor’s Note:

In addition to being a journalist, Jamie Reno is a three-time survivor of stage IV non-Hodgkin’s lymphoma and national advocate for cancer patients and their families. His acclaimed book about a boy who is coping with his mother’s cancer is called “Snowman on the Pitcher’s Mound.”