John Stamos Shares Heartbreaking Tribute to Bestie Bob Saget, Last Pic Together

Bob Saget would have turned 70 over the weekend ... and his best pal John Stamos made sure fans remembered.

Via a series of pictures through the years -- including the last one taken together before Bob's untimely death -- Stamos told fans he misses Bob horribly ... and that he would have thrown him the most epic 70th birthday party.

It's as sweet as it is sad ... the two becoming best pals through their work on "Full House" -- and clearly staying tight for all the years afterward.

TMZ broke the devastating news ... Bob died in January 2022 ... at the age of 65.