Mark Ruffalo penned a touching tribute to his wife Sunrise Coigney on her 51st birthday on Sunday.

The Avengers: Endgame star, 55, took to his Instagram page on Sunday to post a montage of his longtime partner and “best friend”, including an adorable photo of Mark taking a photo of Sunrise as they sat at a dinner table together.

“Happy 51 to my best friend, my partner in all, the most fun and exciting person I have ever known,” the actor wrote in the caption. “So happy we found each other and held on for dear life through everything that came and has left.”

He added, “It’s good to know you and be known by you. The world is a brighter place in your presence and beauty. Happy happy birthday, pal.”

The couple first met on a Los Angeles street back in the late 1990s.

They tied the knot in June 2000 and celebrated their 23rd wedding anniversary earlier this year.

Mark and his wife share three children – Keen, 22, Bella, 18, and Odette, 15.

– Cover Media