It was very important to us in Captain America: The Winter Soldier that their relationship would be platonic. That was what we thought was interesting, because they care deeply for each other but it’s not a romantic relationship, which would be the expected relationship. We wanted to play against that. But they do care very deeply for each other, I think as much as any two characthers in The Avengers do and I think you’ll see that again in Civil War. His relationship with Natasha is important in the movie and I think two of the most endearing scenes in the film are between Steve and Natasha. And of course, that relationship will cary forward into Infinity War. And, you know, that’s our interpretation of the relationship, that this is a brother and sister or a work-husband work-wife [relationship]. And they have a real respect for each other but hey also, because they are very different, the admire those differences in each other and they find a commonality in them.

                                                                                                                 - Joe Russo