Family and friends celebrate WIll's birthday with chocolate and a giant cake!

The kids go sledding during their family vacation in Vermont.

Will and Zoey experience snow for the first time.

Bill and Jen go out to dinner to discuss Jen's job offer and what it means for their future.

Bill and the kids shop for toys to donate to families that are less fortunate.

The family gets into the holiday spirit by decorating the Christmas tree!

While writing letters to Santa, Will and Zoey receive an unexpected call from the man himself.

The family attends a pet adoption event at Bill's store.

Jen helps the kids make Bill a giant birthday card.

Will and Zoey have their weekly swim lesson with Jarrod.

Family story time turns into a discussion on what it means to be a little person.

Bill and the kids hit the grocery store to buy ingredients for his birthday dinner.

Will and Zoey take the wheel as they head out trick or treating with their parents.

With Jen's best friend Amy in town with her kids, the group heads to the local boardwalk aquarium.

Will meets with his speech therapist Anna.

Jen and Bill take Will and Zoey to the geneticist for a check-up.

Zoey loves animals so much she climbs into a cage during her visit to the Childrens Museum.

Watch the moment that Jen found out from her doctor that she has beat cancer. Her heavy treatment paid off and her prognosis is excellent.

Will the Pop Up Pee Pad Be a Success? Rock Tests It Out.

What a crazy, emotional year 2013 has been for the Kleins! Get all of Jen & Bill's best moments with Will in one moving and inspiring video!

Zoey goes down the slide at the Childrens Museum with a little help from Jen.

The Little Couple family is in San Francisco, so Bill, Jen, Will, and Zoey all head to Fisherman's Wharf to see the sea lions and have some fun!

Bill hangs Will's growth chart in his room and Will tries to be a good helper, but as a four year old boy, he is easily distracted.

The dogs rock the runway for Bill's doggy fashion show to benefit local animal rescue centers and shelters.

Bill and Jen meet with Dr. Boostanfar of the HRC Fertility Clinic to discuss their options in their pursuit of having a child.

Will has been able to feed an elephant and a giraffe in the past few months. Bill remembers the time they met the elephant in Mumbai.

Jen shows off her muscles in this push up challenge.

Jen meets with a physical therapist about improving her muscle strength and mobility.

Bill gets a special birthday surprise from Jen.

Will and Bill check out some trains in Grand Central, while Bill's Mom, Jen, and Zoey do some window shopping.

Will & Zoey have a blast at Mt. Vernon playing the old fashion game of stick and hoop.

It's time for Bill to focus on the big doggie fashion show his pet store is presenting. Will the crowds turn out and will Bill and his team be able to pull off this ambitious undertaking?