The Falcon and the Winter Soldier: Anthony Mackie Shares Adorable BTS Photo in Honor of Sebastian Stan’s Birthday

Sebastian Stan, the actor known best for playing Bucky Barnes/The Winter Soldier in the Marvel [...]

Sebastian Stan, the actor known best for playing Bucky Barnes/The Winter Soldier in the Marvel Cinematic Universe, turned 39 on August 13th. Many friends and fans took to social media yesterday to honor Stan, including his The Falcon and the Winter Soldier co-star, Anthony Mackie (Sam Wilson/Falcon/Captain America). Mackie posted a fun behind-the-scenes photo from the Disney+ series and shared some kind words for his onscreen partner.

"@imsebastianstan remember that time I had to tell you i love you from 2 meters away?! Happy Birthday Playa… you are truly the vanilla ice cream in my ice cream sandwich! #AvengerBoyzForLife," Mackie wrote. You can check out his post below:

Stan can currently be heard voicing Bucky in the first episode of What If...?, which premiered on Disney+ this week. Mackie is not one of the many Marvel stars on the What If...? cast list, but it's currently unclear if someone else is voicing Sam Wilson or if he's just not a part of the series. However, Mackie will return in a live-action capacity now that Captain America 4 was announced after the finale of The Falcon and the Winter Soldier. During a previous interview with EW, Mackie revealed that he found out about Captain America 4 from a grocery store clerk.

"I literally found out yesterday in a grocery store. The checkout guy named Dwayne, a cool cat, he's like, 'Yo, man. Is this real?!" [holds up a cellphone] "I'm like, 'I haven't heard anything.' That's what I love about working for Marvel. They call you, they're like, 'Come to L.A. We wanna tell you what's going on.' So, I'm excited to see what happens, but I haven't heard anything."

As for Marvel's What If...?, you can check out the full cast list below:

Andy Serkis, Angela Bassett, Benedict Cumberbatch, Benedict Wong, Benicio Del Toro, Bradley Whitford, Carrie Coon, Chadwick Boseman, Chris Hemsworth, Chris Sullivan, Clancy Brown, Clark Gregg, Cobie Smulders, Danai Gurira, David Dastmalchian, Djimon Hounsou, Dominic Cooper, Don Cheadle, Emily VanCamp, Evangeline Lilly, Frank Grillo, Georges St-Pierre, Hayley Atwell, Jaimie Alexander, Jeff Goldblum, Jeremy Renner, John Kani, Jon Favreau, Josh Brolin, Karen Gillan, Kat Dennings, Kurt Russell, Leslie Bibb, Mark Ruffalo, Michael B. Jordan, Michael Douglas, Michael Rooker, Natalie Portman, Neal McDonough, Ophelia Lovibond, Paul Bettany, Paul Rudd, Rachel House, Rachel McAdams, Samuel L. Jackson, Sean Gunn, Sebastian Stan, Seth Green, Stanley Tucci, Taika Waititi, Tilda Swinton, Toby Jones, Tom Hiddleston, and Tom Vaughan-Lawlor.

Captain America 4 does not yet have a release date, but you can catch new episodes of Marvel's What If...? on Disney+ on Wednesdays.