We quite often talk about my T's children, as well as my own child. For me it's fair natural and 'normal' but at times it does evoke jealousy-type feelings. And what I'm learning that it's important, and welcomed that I talk about all my thoughts and feelings not matter what the precursor. I am also FB friends with my T and we have recently talked at length at the feelings that can bring up, both 'negative' and 'positive'.