I was chewing this over with a friend who is a mum of 2 DDs (I have DSs) Her DS1 (just 4) keeps asking for play makeup. friend wasn't willing to get it for her. I feel sympathetic when considering the very disturbing sexualisation of small girls' clothes etc aspect but also see that there is a lot of creativity in messing about with makeup or facepaints. plus lots of other adult behaviour is modelled in play.
we wondered how other MNers found this issue