Credit: Instagram

It's time to celebrate for Real Housewives of Orange County's Slade Smiley, Gretchen Rossi, and little Grayson!

Slade's son Grayson turns a year older today, and Gretchen took to Instagram to wish him a great one.

"Happy 13th birthday to the most amazing little boy in the world!" Gretchen touchingly writes. "Grayson!! Your Dad @sladesmiley and I love you very much!! #bestkid #suchajoy #soblessed"

"Praise God every day we still have with him!" she continues.

Along with the message, Gretchen posted a downright adorable photo of Slade and Grayson together, with Grayson putting his arm around Slade. Awww! What a great father-son bonding moment.

Grayson is certainly a trouper, having suffered from the neurological disorder diffuse fibrillary astrocytoma. He underwent a procedure last fall to debulk the size of his brain tumor.

As we've seen on the show this season, Grayson's struggle has been tough on both Slade and Gretchen.

"Please continue to uplift Grayson and pray for him," Gretchen wrote shortly after the surgery in October 2012. "Thank you dearly from the bottom of my heart.”

It's great to see Grayson in such great spirits on his special day. We're wishing him all the best on his birthday, and we hope he has a speedy recovery!

Source: Instagram