Look at that smile, E loves construction sites, so I built the items from the front of the box (I LOVE Duplo and Lego) and sat back and enjoyed the rest (I'd just had a naughty wisdom tooth extracted).
Within 5 minutes, the smile disintegrated into shrieks, frustration and anger. Then N woke up from his nap and all hell broke loose. My one-car-each plan didn't work.
In the following weeks I have had to implement rules about when we can get the bloody stuff out, not after nursery, not after 3pm, not when we are about to go out.... Basically, not if I have to deal with the fallout.
Anyway, E loves Duplo but it also makes him pretty frustrated because it falls apart. I love my toddlers, but they sometimes fall apart and make me flap my hands and make frustrated noises.
I am currently fighting the urge to buy another, identical set as it is as likely to end in E wanting it all and N *still* not getting to play with a toy that he enjoys.
There you are, that is my theory.