Check who's nua-ing on bed

Here's Ian lying on his bed just to play with the tissue which he has pulled out from the tissue pack...wonder how he learnt to nua on bed...coz these days mama would see Ian picking something from the side table and the next moment he would be checking his mattress and then lean back and lie down playing with his new found 'toy' hhmm just amazed how he knows he can rem that his mattress is safe to just fall back and lie...just worried he would do it some day on the concrete ground....ouch!