Clint and Steve had always surprisingly gotten on, despite their shared crush on Natasha. However, unlike Clint, Steve never acted on it. He saw love as a distraction from his duty to protect the city as an Avenger, so he gave Natasha to Clint, reluctantly but rightly.
After many months of finally dragging himself to get over Nat, you came into his life. Clint had come back to the compound after a day out with you, and introduced you as his sister. And god, did Steve have to take a double take. You were beautiful, especially to him. The man who had tried to draw himself away from love his whole life after being too insecure to act on it at first, and then too focussed on his new life.
But he was sure you could change it.. for some reason.
The avengers had a party to celebrate your arrival to the team. You were accepted almost instantly, with your insane accuracy skills as well as determined personality. You were everything Steve wanted, and the moment you stepped into his life, he never wanted you to leave.
He knew Clint would probably not be happy about Steve’s building crush for Clint’s sister.. but regardless, that didn’t stop him. Nothing had stopped Steve so far, so why should it now?