Harry Styles bonds with both of his siblings - Thanos included - in a funny birthday post from his sister. Former One Direction member Styles has made quite a name for himself since going solo. In addition to his still-thriving music career, the singer is now turning out to be an in-demand actor. He made his onscreen debut in Christopher Nolan's Dunkirk and will next be seen in this year's Don't Worry Darling, Olivia Wilde's newest directorial effort. Styles also has My Policeman coming up, which will unite him with The Crown breakout Emma Corrin.

On top of all that, Styles' buzziest project yet came just last fall: Marvel's Eternals. He became the latest big name star to join the MCU, appearing in the post-credits scene of Chloé Zhao's millennia-spanning epic. Styles plays Eros, the god of love and, much to fans' surprise, brother of Thanos. Though his role was supposed to be kept a secret, his casting was leaked immediately after the Eternals premiere. Nevertheless, the Eternals post-credits scene drummed up a lot of conversation online following the movie's debut.

Related: Where Harry Styles' Starfox Was During The Infinity Saga

Many fans were amused that Styles is now playing the brother of the purple-skinned, Mad Titan Thanos, and evidently they are not the only ones. On Styles' birthday, February 1, his sister Gemma posted a sweet picture of herself and the singer... and Thanos. It truly is a sibling reunion. "Wishing a joyous happy birthday to my favourite brother xoxo," she wrote in the caption. You can see the full post below.

Click here to see the original post.

Naturally, there's now much interest in Eros and the relationship he had with Thanos prior to the Eternals after-credits scenes. Thanks to both Avengers: Infinity War and Endgame, Thanos remains one of the MCU's top villains, and the revelation that he has a brother hasn't been taken lightly. So far, though, Eros has only appeared in that single Eternals scene, so much of his backstory, knowledge, and personality remains a mystery.

Most likely, all that will be fleshed out in future MCU installments. An Eternals 2 hasn't been explicitly confirmed just yet, but several stars have hinted at their upcoming returns. Additionally, it would be hard to imagine Marvel casting a celebrity of Styles' stature in a role like Thanos' brother for just one scene in the middle of some credits. Both Styles and Eros will be back; the question is just when. Hopefully, Marvel fans will get the answer to that fairly soon. In the meantime, they can enjoy the playful joke shared by Styles' sister and wonder what kind of birthday celebrations Thanos and Eros have shared together.

More: How Harry Styles In Eternals Sets Up Thanos' MCU Return

Source: Gemma Styles/Instagram