One possible way is "while at it" meaning ("while this is the subject of conversation", "while we're on this subject"). And it´s likely that there are other ways, but that springs to my mind right now.
It worth mentioning that those are used generally in colloquial contexts, that is, not usually used in formal settings/writings.
Anyway, there´s the "since we are gossiping, etc...":Well since we are gossiping…I heard that j-lo's soon to be ex was married when they met and he left his ex wife for them to be together.
Foi bom você tocar nesse assunto, pois eu tenho um segredo para te contar.
Could be expressed like this: "since we are gossiping, I have a secret to tell you...
" (and to all Flamengo, Vasco, Botafogo and Fluminense supporters...