On Thursday, April 10, the Full House alum, 61, celebrated his son Billy's 7th birthday — and his wife ... "Today our Billy boy turns 7. SEVEN," Stamos began. "A magical, chaotic, hilarious ...

"Happy 7th to our boy," he added. "And happy birth day to the one who made him. We see you, Caitlin. And we love you." Never miss a story — sign up for PEOPLE's free daily newsletter to stay up ...