As someone who likes to break into things (legally, with permission, blah blah blah) I can assure you that no amount of locks will keep a determined individual from something, especially if they know the schedule of the people they're concerned about and if they have an effectively unlimited time with the thing they're breaking into.

Locks will deter, not prevent, theft or unwanted handling. If there's a way to access it, it is accessible to anyone with time and intent.

I like picking locks and even if I don't have the skill for a certain lock, I've opened them by accident just by trying over and over. I just needed time.

A gun safe by itself is not enough.

A locked door is not enough.

I know someone who used to take the firing pins out of every firearm, which would then be in a locked box in a floor safe under his bed. Guns in a locked safe, with a locked closet and locked room door. That was when he had nieces and nephews that came over a few times a month. Once he had his kids, the guns went to storage at his dad's house. His reasoning? He used to steal alcohol from his parents cabinet as a teen and they tried many many times to make it harder but he always managed to get to it. "I always found a way, so could my daughter"

My own firearms have cable locks through the chambers, they're locked in a keyed safe, and the safe is in a locked closet. The only copy of the safe key that isn't either on me or my wife is in a hollowed out 2x4 that looks like it's part of the ceiling in my attic just in case I ever lose my key but need into it.

I don't have kids so I'm not concerned with someone who has a lot of time on their hands, but never underestimate how determined someone can be when they're told "you aren't allowed in there"

All of this is basically to say "the only way you're keeping someone permanently away from the guns in your house is to NOT HAVE GUNS IN YOUR HOUSE"

Unrelated,

which was in my person at all times.

Sorry the phrasing just gave me a giggle.