The reality star announced she was leaving 'Teen Mom 2' in November.
Chelsea shared two adorable pictures of Walker, noting that she has the same birthday as their 3-year-old son, Watson. The 29-year-old reality star is also a mom to their 1-year-old daughter, Layne, as well as her 10-year-old daughter, Aubree, whom she shares with her ex, Adam Lind.
"Walker June 6lbs 1oz 🌻," she captioned the sweet photos. "She decided she wanted to share a birthday with her big brother, Watson and surprised us by coming last night."
In November, Chelsea announced she was leaving the show after nine years as an original cast member. ET spoke to her in August, when she talked about proving stereotypes wrong and setting a good example after getting her start on Sixteen and Pregnant, then later, Teen Mom 2.
"It was either I can be this stereotypical or whatever anyone thinks of a young mom, or I could prove them wrong, you know?" she explained. "And even if I didn't have the show, like I did, I wanted to go above and beyond and prove people wrong. I've always wanted to be a mom, this is what I always wanted in life."
The South Dakota native also talked about the reaction she got when announcing she was pregnant with her fourth child.
"There's always the comments that are like, 'She's pregnant again?!'... I think a lot of people still consider or think of us as being these young or teen moms," she said. "Did you see the one where someone said to keep my legs closed or something? I was like, I mean, I'm married so... It just cracks me up. People just don't realize that we are almost 30, I think, and married, and we're not teenagers anymore."
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