I cant speak for myself but I just wanted to let you know, my littlest brother was BF till 18months, mum weaned him straight to cows milk in one day, BUT- he continued to stick his hand down her top and feel her breasts until he was at least 8! (poor mum copped a lot of flak myself and my other 2 brothers for this, but as mum tried to explain to me then and I now understand now, it was just a comfort thing.
Dont know if that helps, but oh, also my nephew is now 5, BF till 13 months, still tries to do the same to my SIL.