ROYAL OAK, Mich. – It's hard enough for most parents to imagine having one child who needs brain surgery, but imagine having two.
That's the frightening situation Kim and Aaron VanBaak from Utica, Mich., recently faced.
Watch: Siblings recovering from brain surgery
The VanBaaks have three children -- 7-year-old Zoey, 6-year-old Gracie Claire, and 5-year-old Parker.
At first glance, the kids look happy and healthy. But Zoey and Parker have suffered for years with a painful condition that few people have heard of.
"We knew something wasn't right with Parker from the day he was born," said Kim.
As an infant, Parker was diagnosed with a collapsing trachea and other issues, but Kim said nothing ever quite explained his symptoms.
"He started doing this odd thing where he would rock, in my rocking chair," said Kim. "He would suck on his two fingers, and he would literally rock holes in the wall, just rocking and rocking and rocking."
After years of searching for answers, it was an MRI that finally revealed the cause of Parker's problems.
"The woman called and said, 'He has something called a chiari malformation,' and I'm like, 'A what?'"
A chiari (kee-AHR-ee) malformation is a disease of the brain in which brain tissue is pushed down into the spinal canal. It occurs when the hole at the base of the skull is too small or misshaped, pressing on the brain and forcing it downward.
Chiari malformation can cause a blockage in the flow of cerebrospinal fluid (CSF), which can cause the normal fluid spaces in the brain to enlarge.
A chiari malformation can happen before birth or develop later, as the skull and brain are growing.
Some chiari malformations are mild and cause no symptoms. Others are severe and cause a wide range of painful problems.
Parker suffers from frequent and severe headaches.
"It goes to my forehead to my feet," said Parker.
The VanBaaks discovered Zoey also suffers from a chiari malformation.
"Once we realized what Parker had, I started reading, researching, determining well these are the side effects, and I was like, "Whoa, Zoey fits a lot of these,'" said Kim.
Zoey's chiari malformation causes many symptoms, including leg pain, trouble swallowing and poor coordination. Zoey and Parker have found support in each other.
"He knows, like how I feel when my legs hurt," said Zoey. "And I know how he feels when his head hurts."
The VanBaaks found hope in Beaumont Hospital pediatric neurosurgeon Dr. Holly Gilmer. Gilmer says chiari malformations are not as rare as they might seem.
"It occurs in about one in a thousand live births. That number is really based on known chiari, patients who are symptomatic," said Gilmer.
It's believed as many as 20 percent of the population actually has a chiari malformation, but most will never experience symptoms.
Gilmer told the VanBaak that to ease their symptoms, Parker and Zoey would both need surgery to open up the crowded space at the bottom of their skulls. And she had a stunning suggestion -- do the surgeries on the same day.
"At first, we told Dr. Gilmer, "No thank you,'" said Kim.
"I thought about the parents having to take off time from work twice. Having to be home with the kids twice. And then, more importantly, one little one watching the other little one go through it, knowing my time is coming up," said Gilmer.
"When you think of it, it makes more sense," said Aaron. "And plus, if you're going to divide them up, which one do you do second, which one do you make suffer longer?"
As for who would go first --
"I'm going first. So my sister Zoey can see how it is. 'Cause I did it before," said Parker.
"At first I was a little scared," said Zoey. "But then, Mommy told me that it wouldn't make my legs hurt so much anymore."
In April, Parker and Zoey had their surgeries back-to-back at Beaumont Hospital in Royal Oak.
With Parker in the operating room first, the family tried to focus on distracting Zoey.
"The little ones want to play their games and color, so doing that with them, you know, helps a lot to take your mind off of it," said Aaron.
"You worry about perhaps something going wrong," said Kim. "But you don't want to be too upset, because you don't want them to feed off your anxiety, your fear. So it's a lot to control around them."
Three hours later, it was Zoey's turn. As surgeons began her operation, word came that Parker was out of the OR. His surgery went well, but doctors found Parker's condition was worse than expected. It was news that brought Kim to tears.
"He was suffering," said Kim. "And that's hard to hear."
Just three days later, Parker and Zoey were ready to leave their shared hospital room.
The surgery is not a cure, but the VanBaaks hoped it will relieve the kids' symptoms.
In the two months since their surgeries, Parker and Zoey have seen improvement.
"There is some pain, but it is just amazing at how much better they are in such a short amount of time," said Aaron.
Parker's headaches are less frequent and severe, and Zoey has made huge strides in coordination. Before surgery, she couldn't drink from a regular cup. Now, she can.
"To see her drink out of an open cup is just amazing," said Kim.
Zoey and Parker have helped each other through their recovery.
"It could have been worse if I was by myself probably," said Zoey.
As for how they're feeling, Parker can sum it up in a single word, "Good!"
The family's joy has been tempered by a stunning discovery. Doctors now say both Kim and the VanBaaks' other daughter, Gracie, both have chiari malformations too.
The family suspected Kim was affected, but was badly shaken by Gracie's diagnosis.
"Knowing the possibility is there for Gracie also, you know, is difficult," said Aaron.
"I don't like it," said Gracie. "'Cause I don't want to be in pain."
Because Gracie's symptoms are mild, doctors will simply monitor her for now, but Kim will probably need surgery herself at some point. For now, the VanBaak family is focused on the kids and raising awareness of chiari malformations.
"It's difficult. You never know what day to day holds," said Aaron. "Every day that you get through it makes it that much more rewarding. It's amazing how certain things bring people together and how much people care."
"I just want people to understand that this is what chiari is, and that there's a lot of people out there struggling with it," said Kim. "We'd love someday for there to be a cure. We need to conquer chiari."
Help The VanBaaks:
The VanBaak family is facing a lot of medical bills. To make a donation, go to any Huntington Bank and ask for the Zoey VanBaak Chiari Fund or the Parker VanBaak Chiari Fund.
A bowling fundraiser for the family is planned for June 2nd and a golf outing for September 7th.
The VanBaaks said they are grateful for all of the support.
Learn About Chiari Malformations:
To learn more about chiari malformations, visit the Beaumont Neuroscience Center of Excellence and the Conquer Chiari website.
Support Groups:
For more information on the Southeastern Michigan Chiari Support Group, click here or visit their Facebook page.
Beaumont Hospital is also offering a new monthly support group for those with Chiari malformation, starting June 13.