Tell her a gun is like a tool. For every size bolt there is a wrench made to fit. Same for firearms. For every type of gun there is a special use.
Tell her big boys play with big toys and you have a new hobby that might just save her life some day. Few things can put meat on the table and protect your life at the same time.
She’s heard those before, and the “tool” one she’s heard several times. I’m going to have to be more creative. That and realizing the money already seems to be gone. :^(