I just want 5 minutes alone!

How come whenever my OH leaves DS alone for 5 minutes he gets into absolutely no trouble at all? Even for longer periods. Yesterday morning I was reluctant to get out of bed after spending half the night tossing and turning dreaming about school exam results (DS's not mine, he's not even 4 yet!). DS wanted a particular toy that we'd taken out with us the day before so I instructed him that it was in the bag in the hall - he eventually came back with the toy and I thought nothing of it. However when we ventured downstairs I discovered that we actually couldn't get into the hall - at the bottom of the stairs was an almighty mess. A kitchen chair had been dragged through and used to reach my handbag from it's place on the peg by the door, my gym bag, his swimming bag and his nursery bag had all been upended and the contents mingled with that of my handbag.

Then this morning OH is out at the crack of dawn and so I have no other choice than to leave DS whilst I have a shower. I come out of the bathroom to see him proudly showing off his hand - he's climbed the furniture to retrieve my shocking pink nail polish and has painted the fingers of his left hand with it (from knuckle to tip). I don't know what worried me the most, his climbing the furniture, the chance said furniture could now be covered in fuschia pink nail polish or his desire to do it in the first place. I've not taken it off yet so my OH can see exactly why I can't leave him alone for 5 minutes!!