The 6-year-old stepdaughter doesn't need to see Stepdad hanging in his underwear, no matter what kind it is. Boxers can also reveal quite a lot of what's in them.

The LW should talk to her daughter and ask her why the man cannot wear pants around other people. Yes, it's his home. It's also his children's home.

LW should stop viewing this as a personal affront and start considering it a boundary violation. She should continue with the child care and listen carefully to them.