Amy Sussman / Invision/AP 1 / 5
Amy Sussman / Invision/AP 1 / 5

When Sarah Chalke isn't in front of cameras filming her new TV show "How to Live With Your Parents (For the Rest of Your Life)," she's been playing with cars with her 3-year-old son, Charlie, and she wouldn't have it any other way. "That's his favorite thing in the world right now," Sarah told Wonderwall. "The second we wake up in the morning, he'll say, 'Let's play cars,' and we'll play for hours."

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Spending time playing with her only child with fiance Jamie Afifi is a welcome change of pace from how they have spent countless hours with young Charlie -- in hospitals and clinics. The actress recently revealed that Charlie suffers from Kawasaki disease, an illness that causes inflammation in a child's blood vessels. Her harrowing medical journey recently served as the inspiration for a "Grey's Anatomy" storyline that aired on March 28, 2013, featuring Sarah in a guest-starring role.

"The response from parents who have dealt with it has been overwhelming," Sarah said. "That's been one of the neatest parts of this experience that I hadn't really thought through. It reinforces the need to raise awareness because it's a lot more prevalent than we think."

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In addition to the "Grey's" episode, Sarah also spoke at an event last year to help raise the profile of the disease, which can lead to life-threatening ailments like heart disease if not treated properly. "It was obviously the hardest thing that I've gone through ... and before I spoke at a fundraiser in November, I had never met anyone who had been through (Kawasaki disease) in the year and a half since we had," she revealed. "It was a really powerful experience and out of that experience and out of meeting parents who didn't have as lucky of an outcome as we did -- our son's heart is OK -- that made me feel like we needed to do something to raise awareness on a large scale."

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Now that her son is healthy, Sarah has been able to focus on returning to the small screen opposite Brad Garrett and Elizabeth Perkins in "How to Live With Your Parents," her first series regular role since the long-running hit show "Scrubs."

"Comedy is always healing," she admits. "It's another reason I love it -- why I love going to work. … I'm having a blast."

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