Just that really...my nearly six year old and 4.5 yr old have been pretty interested in their and each other's willies and bums for about a year now. Mainly kicks off in the bath and initially I ignored it, then my mums advice was to get them to lick other things like soap, the sponges, bath toys, (as opposed to each other's bottoms) and occasionally they don't do it, but I would say on the whole it is a fairly consistent theme. Before I know it, one will have his bum thrust in he the air and the other will be trying to lick it. Now, my dh and dm say this is normal. I am not so sure. Last night, the older one bit the younger ones bum leaving teeth marks and tonight when I was putting baby to bed, I came in to find the little one was chanting "I am going to lick your willy". Is this the usual anal / sexual phase of development as named by Piaget and Bowlby? How do I react? Am terrified my over reacting will cement this behaviour as something negative in their futures, but equally and worried that under reacting and ignoring it will lead to them 'experimenting' with each other on an increased basis. Or god forbid, other children! Any psychoanalysts, or developmental consultants opinions welcome!