I Rounded Up The Best Marvel Birthday Posts From Robert Downey Jr., Chris Hemsworth And More MCU Alums

When the stars of the Marvel Cinematic Universe are acting alongside each other on screen, they may be playing comrades in arms, friendly rivals or even frenemies. In actuality though, most of the actors seem to be relatively tight friends and show love to one another. One way they do that is by sharing sweet birthday posts on a co-star’s special day. Not every actor or director does this regularly, but there are quite a few MCU alums that have shared b-day posts quite frequently over the years. Beloved Thor star Chris Hemsworth and Iron Man icon Robert Downey Jr. are only two such actors to do this. With all this in mind, I rounded up some of the best tribute posts. 

The ties within the MCU family are strong, and it’s always lovely whenever they reach out to each other over social media. The birthday posts are especially great, because they vary in style. Some can be purely sweet, others can be quirky and another portion of them might just be downright hilarious. Most would probably agree that a good birthday message can really brighten someone’s day. These Marvel posts may not actually be intended for any of us, but they’ll still put a smile on your face nonetheless. On that note, let’s discuss some Avengers alums and recall how they’ve celebrated the days their colleagues were born. 

Robert Downey Jr.

Imagine getting a birthday shout-out from Robert Downey Jr. – Tony Stark himself. The mere thought of that is probably enough to stoke up feelings of envy in anyone who’s not fortunate enough to be in that position. But this fan just enjoys seeing how Downey chooses to express his affection. He’s shared plenty of wonderful b-day posts over the years, sending well wishes as only he can. Someone who’s been on the receiving end of that kindness is Gwyneth Paltrow, who played his on-screen partner, Pepper Potts, for over a decade. While there are plenty of Paltrow-centric posts to choose from, one of the best comes from 2018, and it’s caption includes a funny callback to The Avengers: 

Another person who’s received a great tribute is Josh Brolin, as RDJ honored him by sharing a behind-the-scenes photo from 2018’s Infinity War. The snapshot he shared provided an inside look into the brutal showdown between Tony and Thanos during the film’s third act. And the Sherlock Holmes star – being the clever person he is – dropped an A+ pun that references a Brolin movie: 

Of course, Robert Downey Jr. has also given his share of props to the late, great Stan Lee. The star would do that even before the late comic book guru died in 2018 and still does so now. Downey’s posts in Lee’s honor remain incredibly special and are more than worthy of the self-proclaimed “King of Cameos.” The one he shared in 2020 was especially delightful, as it featured a BTS photo from 2016’s Captain America: Civil War and nodded at a great joke from that film: 

Whether or not Tony Stark truly had a heart has been humorously debated within the MCU for years. However, there’s no doubt here that the actor who played him possesses a heart of gold and a particular soft spot for the people he works with.

Chris Hemsworth

You can’t help but get the feeling Chris Hemsworth loves birthdays, based on how he typically takes the opportunity to mark his own or wish someone else well on their special day. He celebrated one of his most recent b-days by chowing down on a “marvel-ous” amount of cake, and he posted about it. The tributes he sends to others are just great, as he usually pays tribute by making jokes and/or sharing funny photos. Check out the following message he sent to Robert Downey Jr. if you need evidence: 

He’s also sent love to Chris Evans on a number of occasions, and there’s a running theme when it comes to those posts. The Extraction star likes to reference the “Best Chris” debate in his message, and they’re too funny. Look at this cheeky one from 2021: 

And if you think that one was funny, you need to check out another one shared for his fellow Chris in 2023. Peep the following: 

Needless to say, Chris Hemsworth has a great sense of humor, and I don’t see it going away anytime soon. What also seems endless is the debate over the best Chris is. But if you ask me, I’d say Hemsworth is making a strong case for the title with his b-day posts alone. 

Jeremy Renner

We also have to give some serious props to the man who’s portrayed Clint Barton a.k.a. Hawkeye for more than a decade – Jeremy Renner. He’s also become quite close with his Avengers co-stars and has shared some sweet moments with them over the years. With that, he too engages in the lovely ritual of honoring his favorite friends on their birthdays. Many of his posts are relatively straightforward, but generous, while others are a bit more creative. For instance, when he wished Robert Downey Jr. a happy birthday in 2023, he reminded his co-star (and the public as well) that his snow plow incident wasn’t the first time he’s ever been on crutches: 

That’s a memorable post, but it has nothing on the one he shared when friend and fellow Marvel alum Paul Rudd turned the big 5-0 in 2019. That’s a major occasion, and the Mayor of Kingstown star definitely celebrated with a message that Rudd (and fans) surely won’t forget: 

For the record, I’d pay good money to see that movie, but I digress. Jeremy Renner’s b-day post game is definitely solid, though I’d still say there are some other colleagues of his that really take the (birthday) cake in this regard. 

Joe And Anthony Russo

That’s right, Joe and Anthony Russo – the sibling filmmaking duo who helmed Captain America: The Winter Soldier, Civil War, Avengers: Infinity War and Endgame – also participate in this ritual. You may not think it, but the two brothers are actually very good at bestowing birthday greetings upon their pals. Do you need evidence of that? Well, check out the A+ way they shouted out our friendly neighborhood Spider-Man actor, Tom Holland, on his 27th birthday: 

The two can also be sentimental, of course, and that was the case when they wished Jeremy Renner a happy birthday in 2023. Joe Russo’s daughter, Ava, actually plays Clint Barton’s daughter, Lila, in the MCU, meaning Renner is her on-screen daughter. And Joe referenced that in a particularly lovely way:

But again, above all else, it seems the Russos have plenty of jokes and don’t mind getting flat-out weird when it comes to their posts, too. Take a look at how they commemorated one of Chris Hemsworth’s b-days: 

Yeah, I’m never going to get that clip out of my head, either. As weird as it may be though, it’s a testament to the creativity Anthony and Joe Russo possess when it comes to crafting celebratory content. 

Sebastian Stan

You may not believe this, but Sebastian Stan (who plays Bucky Barnes/ the Winter Soldier) is one of the best when it comes to showing birthday love to other Marvel actors. Like those of his peers, he’s able to be both sentimental and funny when posting his thoughts. The former really shown through when he wished friend (and on-screen rival) Anthony Mackie a happy birthday by sharing a BTS video: 

The Fresh star is also very supportive of his colleagues’ endeavors, whether they be MCU-related or not. For example, he paid tribute to good buddy Chris Evans (and his mustache) when he name-dropped The Gray Man in another tribute: 

Sebastian Stan also has a sentimental side that shines through here and there. It was especially evident when he honored late co-star Chadwick Boseman around the day he would’ve turned 46. See the highly generous way he celebrated the life and legacy of the beloved Black Panther icon:

While Bucky Barnes may sometimes have trouble expressing himself, the Sharper actor doesn’t. Kudos to the actor for always taking the time out to shine the spotlight on his friends. 

Mark Ruffalo

So we’ll end this list with the MCU star who has a reputation for spoiling Marvel secrets – Mark Ruffalo. Admittedly, he sometimes does have loose lips when discussing his superhero-related work. That enthusiasm also extends to his habit of sharing great birthday posts for his fellow Avengers. He usually chooses great photos, some of which are taken on the set. Take a gander at his celebratory message for Chris Hemsworth: 

The Oscar nominee continued that trend when he shouted out Josh Brolin in 2021. His photo shows him and Brolin chopping it up on set while in their less-than-flattering “man-cancelling suits.” And the star joked about the attire:

One also has to mention the sentiment he shared for Paul Rudd in 2021. The Hulk actor’s image of choice is great, but it’s the caption that makes it perfect: 

Seriously though, how does that man not age? Anyways, Mark Ruffalo never seems to miss a birthday, and I’m glad he doesn't. His posts are always warm and, in many cases, his co-stars seem to appreciate them. 

Hopefully, as time goes on, these particular Marvel stars and more will continue to send wonderful wishes to their collaborators on their birthdays. A number of the actors no longer appear in the MCU, while others are still in the fold but not popping up as frequently. These posts are great ways to help ensure the bonds between the actors remain solid, and I, for one, am here for all of them. 

Watch the stars in their fan-favorite roles by streaming numerous Marvel Cinematic Universe films using a Disney+ subscription.