2.10yo DS loves having showers and baths with me or DH, and loves cuddling us naked, skin-to-skin. OK-ish, for now.
A few times now, though, he's asked to have a bath with me, ripped his clothes off, and stared fixedly at me when I've been taking my clothes off, then started patting my boobs, while fiddling with his willy before I've even got my clothes off, saying, 'I love you mummy! You're cute! I love you!' (cuddles my leg) then...'I have a long willy!', showing me his erection.

Is this behaviour...um...to be expected? Do I need to stop disrobing in front of DS or having baths with him? It feels rather awkward for me, and he's nearing an age where he might remember it...