I just rewatched “In the name of the brother” – and got reminded of the reaction Emma showed when Gold told her that she has to come searching for his son because “every minute I’m here is a minute closer to me killing Hook”. So Rumple knows too that there is something between the two or he wouldn’t have used Hook to pressure Emma. Also I’m thinking about why they showed us Snow in that moment – to me she looked like a little worried or something… Does that mean that she, too, sensed something there?