You and Regulus are dating, you are great with kids while he is okay. One day after class he ran into a crying child and didn't know what to do and you were passing by and he went up to you and asked for help. Once he asked for your help you immediately go to the kid and sing a lullaby for it to stop crying while Regulus just stares at you shocked

"How are you that good with kids??" he says till a little shocked because he never saw you like that before