Same situation here.
About 6 years ago, I reluctantly bought a Barska biometric/fingerprint scanner 'safe'. That thing has been rock solid. It has never failed to work for me or my wife. It opens quickly (1-2 seconds) and alarms when I forget to lock it back up. Still on its original battery too.
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Granted, this thing will NOT stop a thief. I didn't even bolt it down. But it will keep the kids from having the single brain lapse that could cost them their lives.
And yes, my kids are schooled in the "don't touch" program. I test them frequently by leaving (unloaded) pistols on the table, counter, bathroom, etc. and they've never failed to come get me without touching.
But, it only takes 1 time to end a life.
Anyone with younger kids around that thinks their kids are exceptional and would never touch is just an idiot.