Costars, fellow comedians, and friends — including John Stamos, Josh Radnor, Jon Stewart, Pete Davidson, Ken Jeong, Kat Dennings, and more — are remembering the star after his death at 65.

Bob Saget, star of Full House and America's Funniest Home Videos, died Sunday at age 65. Immediately, reactions from friends, co-stars, and fans poured in, celebrating and remembering the comedian.

John Stamos, who worked with Saget for eight seasons on Full House from 1987 to 1995, as well as the reboot Fuller House, was among Saget's costars expressing their dismay on social media.

Kat Dennings who played Saget's TV daughter on one season of Raising Dad shared her grief over losing their TV dad.

Patton Oswalt shared photos from a recent visit with Saget, where Saget was interviewing him for a documentary, which brought him to tears.

How I Met Your Mother star Josh Radnor, who played the lead character Ted Mosby voiced in the future by Saget who narrated the series, shared a multi-tweet thread highlighting what a great experience he'd had working with the comic, calling Saget "the kindest, loveliest, funniest, most supportive man. The easiest person to be around. A mensch among mensches."

Josh Radnor; Bob Saget; Kat Dennings
Josh Radnor; Bob Saget; Kat Dennings
| Credit: Jean Baptiste Lacroix/WireImage; JC Olivera/WireImage; ROBYN BECK/AFP via Getty Images

SNL's Pete Davidson doesn't have social media, but he asked a friend to share his sweet message about his longtime friend where he recalls how much Saget helped not just him, but his mom during some very hard times.

Saget was a giant among fellow comedians, and many including Jon Stewart, Joel McHale, Marc Maron, Ken Jeong, and more took to social media to express — over and over — how nice and funny he was, as well as their own shock over his sudden passing.

Penn Jillette directed The Aristocrats — a documentary featuring a stacked roster of comedians telling their versions of the bawdy, titular joke — and Saget's was infamously among the raunchiest. Jillette noted that his friend would have wanted him to say something "really funny and in very bad taste" but the actor and magician said he was " too sad" to abide.

The Twitter account for America's Funniest Videos, which Saget hosted from 1989 to 1997, also took the time to remember the beloved comedian.

Truly, everyone who knew Bob Saget, and there were a lot of people, seemed to love him, from television legend Norman Lear to actress Marlee Matlin and musician Questlove.

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