Is not 5 minutes, its an entire trip down 11 floors, "doing stuff" and then back up. What if he/she gets hit by a car crossing the street, how long would he be left alone then? What if he gets hungry? Needs to use the bathroom, slips and cracks his head? A fire? He cant even tie his shoes yet, let alone establish an escape plan.
*sigh*
My ex tried repeatedly to make these types of arguments in court. Now, we're country/suburban dwellers, so the context is slightly different, but the thought process is the same.
I would *repeatedly leave my then 2 and 5 year old children alone inside the house while I mowed the lawn or pasture. I'd put them down for a nap and go work horses in the field, or get gardening done or whatever. Sometimes, they got up while I was outside, and had to come find me.
Sure, it's possible I could have been trampled, fallen in the pond and drowned, been hit by a rogue tractor driving down the road, and the kids would have been alone until my husband got home from work. But the CHANCES of that happening are so slim as to be irrelevant.
There were also occasions when my infant son was down for a nap (when I lived in an apartment) and I'd hand off the baby monitor to the upstairs neighbor, who had a key to my apartment, and head off to the grocery store. I'd be gone for 30-45 minutes, and she'd keep an ear out for kiddo.
I use these scenarios to illustrate to you that "HE'S ALL ALONE AND HE COULD DIE!!!" will come off as a bit irrational.
AND... getting a restraining order because you believe that the other parent's partner is going to behave violently towards your child is either 1) insane or 2) proof that you're willing to leave your child in a violent home as long as the potential perpetrator is PRESENT (not leaving the child alone).