Robert Downey Jr. Helped Jeremy Renner Celebrate His Birthday!

Robert Downey Jr. and Jeremy Renner assembled as Jeremy rang in his birthday!

The Avengers: Endgame co-stars, ages 54 and now 49, respectively, shared an exchange on Instagram on Tuesday (January 7).

“#happybirthday #jrenn @renner4real ,,, I’ll always have your back…,” Robert captioned a photo of the duo smiling as they stand back-to-back.

Robert Downey Jr. added, “#mountainman #americanpicker #manabouttown #nopantsrenner #glassofwine #sayhellotree #jerimiahjohnson #throwback @avengers (📸 @jimmy_rich ) #seoul #korea.”

“Love you brother,” Jeremy Renner commented on the pic. “Thank you for the song and cake last night !!! Made my week ❤️.”

READ MORE: ‘Avengers’ Cast Cement Their Hand Prints Ahead of ‘Endgame’