I'd also caution against letting your kids peek in before you do, ever...as for various reasons (and sooner or later) some mice will chew up some of their kids...
just saying. (Those who think it's terrible that snakes kill rodents should see & consider what mice do to their own sometimes...snakes are kinder, though not
by intent.) Still, it's great to breed your own rodents...I have for many years, I'm proud of my 'herd'. They work hard & are fed well, & it's probably better than
the life of wild mice.