Gaslighting?

Melody • Mom to soon to be three amazing daughters❤️❤️

Posting for a friend. Her husband who's step father to one of her kids and they share one. The father was walking by the kids playing and told one child to kiss and hug the other. When she confronted him about it he said she was overreacting and that he said it in a playing manner and she needs to drop it. That they are siblings so it's not weird. Pretty sure that's gaslighting. Anyway I agreed with her but wanted to hear your thoughts.