you and regulus have both liked eachother since first year, your both now 6th year

Your james potters sister and regulus is sirius blacks brother meaning yous see eachother a lot

Its Christmas and james invited both sirius and regulus, meaning you had to share your room with regulus and you only have one bed

Your sitting downstairs on Christmas eve, eating dinner at the table beside regulus and sirius, james and your mothers on the other side of the table