When I was 19 I only owned one firearm. For about a week. Then I had two. The first gun I bought was a 12 gauge coach gun. Followed by a Marlin 60. Then a Yugo SKS. Then it just snowballed from there.
My sister only owns one firearm. It's a 9mm pistol. She only has it because I bought it for her. I taught her to shoot it, take it apart, clean it. She uses it for home defense. She shoots it on occasion, but she is not a gun person.
My father also only owns one firearm. It's a Springfield 1911 that I bought him. He wanted one, but couldn't afford it. He is not a gun person either, but wants to learn. When I have time to visit him next, I plan on training him.
I don't think anyone in my family would own a firearm if it wasn't for me. They're not anti gun, just don't have much interest in them. I'm working on that.