Over the years, Rudd’s youthful appearance has become the centre of internet memes due to the fact he doesn’t look much older than he did when he appeared in Clueless in the 1990s.
So, when the Ant-Man star turned 52 on Tuesday (6 April), many used the opportunity to share these memes again.
Aniston herself addressed his “agelessness” in her birthday message to the actor, posting on Instagram: “Happy birthday Paul Rudd!! You don’t age, which is weird – but we celebrate you anyway.”
The pair have remained close since starring together in The Object of My Affection in 1998.
Rudd was then cast as Mike Hannigan, the boyfriend of Lisa Kudrow’s Phoebe, in sitcom Friends in 2002.
Both Rudd and Aniston appeared on-screen together again in Wanderlust 10 years later.
Also sharing birthday wishes to the actor were his Marvel co-stars Mark Ruffalo (Hulk) and Robert Downey Jr (Iron Man).