Casey Reinhardt was known as the "new girl" during her Laguna Beach tenure — and now there's a new girl in the MTV alum's life.

The SoCal native just welcomed daughter Kensington Kelly Brown with husband Sean Brown, she happily announced on Instagram. Would you look at that precious bow hat?

"We are beyond in love with our sweet girl and I absolutely love being a mommy!" Casey gushed, along with the scrumptious snapshot of the snoozing newborn. "I feel so overwhelmed with joy every time I look at her...This is what pure happiness feels like. I love you so much @seanmbrown1 thank you for giving me the best gift I could ever imagine! Life is so amazing and we are so blessed."

In addition, Casey — who shared that she was avec child in April — posted a photograph of the trio departing the hospital and complimented her "strongest supporter."

"I have the greatest husband anyone could ever ask for," she continued. "He's been my strongest supporter and the best daddy! I am so lucky to have you as my life partner."

Be sure to offer your congrats to Casey, Sean, and Kensington in the comments!