Handyman

 A toy ran out of batteries, so I told Dylan we needed to put new batteries in it. D was all over that - marching to the battery bin and bringing them back into the room. We needed a screwdriver to open the slot holding the batteries, and D surprised me by being veeery into helping.

Picking out the right size.

 Attempting to open it.

 Moving on to tightening the screws on his crib with Daddy.

Full access. No safety concerns here, right?