Have Mercy! John Stamos is Officially a Father!

America's favorite TV uncle is now a dad himself. 

John Stamos, 54, announced on Instagram yesterday (April 15) he and his wife, Caitlin McHugh, had welcomed their baby boy into the world.

From now on, the best part of me will always be my wife and my son. Welcome Billy Stamos (named after my father)  #NotJustanUncleAnymore #Overjoyed

A post shared by John Stamos (@johnstamos) on Apr 15, 2018 at 10:30pm PDT

The baby, whose name is Billy Stamos, was named after John's dad. Back in December, John shared this emotional tribute to his father on Instagram:

I will certainly fall short of the father my pop was, but - I’m going to give it my all! #Balance #BillStamos #Hero

A post shared by John Stamos (@johnstamos) on Dec 15, 2017 at 6:50pm PST

"I will certainly fall short of the father my pop was, but - I’m going to give it my all," he wrote.

Stamos began dating the 32-year-old actress back in 2016. The pair got married during an intimate ceremony in early February.