Saget thanked Stamos for being there “even when I could be unbearable.”

“Today is a special day.

“To say we are like brothers is an understatement.

FULL HOUSE

Bob Saget and John Stamos.ABC Photo Archives/Disney General Entertainment Content via Getty Images

We have been through so much together for 35 years.

High, lows- The usual you go through with [the] closest of people in your life.”

He has always been there for me.

Even when I could be unbearable.

Anyone who knows him knows what a beautiful person he is.

And I’m not talkin' about his gift of looks.

I’m talking' about the gift of his heart.

He deserves the happiest birthday of birthdays.”

Happy Birthday, Dear John."

Have mercy (on our hearts).