I can totally see when Bucky gets better and in his right mind Steve teaching him that even though they were on ice they are old and can boss around any person any age 

Dont you just see Bucky and Steve being stupid jerks and punks with each other and the avengers are like ‘what the cap is fun?!’ so Bucky and Steve make a game of saying 'Son just don’t’ to people.

After playing for a couple weeks Bucky wants to win and when Fury is screaming about something Buck goes 'Son just don’t’ and makes Steve laugh till he’s coughing…

Yep if you’re friends with Steve you will learn the 'son just don’t ’