Keep It To Yourself
I have a teen (adult, but still teen) daughter.
She knows I have a few rifles. She's been to the range with me and shot the 10/22 and the Savage MkII.
She has unbelievably poor judgement in friends.
After she went through her third set of friends, and the pattern became clear, I resolved that I would not tell her about my pistol or her mom's pistol. Coincidentally, at this same time, I suddenly got a hankering for a lockable gun safe (RSC).
Oddly, she herself can be trusted with many things, but she doesn't get that some of her friends are . . . broken. So, the simplest way to keep it from her friends was keep it from her.
Information Security is your first layer of protection.
Don't give it up.