1.) The black sisters used to have sleepover like every weekend and doing sleepover stuff like braiding somebody hair,talking gossip and stuff and maybe planning a plot to kill somebody yk girl stuff
2.) When younger they used to the trio of sister used to be like reallllly close to each other but then THINGS happen and they werent anymore they also miss what theyre relationship used to be btw
3.)They share their stuff all the time like “Yo sis can i have an eyeliner I lost mine” “sure”
4.) Narcissa acts like the older sister typa stuff even though shes the middle child shes like the one who sets disipline to her sibling and stop them from doing crazy shit all the time and this type of behavior also helped her when hse became a mom to yk Draco
5.) Bellatrix is the crazy sister like the sister who gets into fights or duels more often and that type of stuff but also really overprotective one of my personal favorites is Lucius getting cursed by Bellatrix because she thought he was trying to play Narcissa heart with Andromeda in the backrounf trying to stop it
6.)Andromeda is the kind and caring sister in the family but is also Narcissa and Bellatrix combined in one body cause yk double the trouble except its two personalities in one person
7.) Andromeda hated devination so much I mean at first she gave it a try but then thought it was nonesense then left kind of like hermione yk
8.) Bellatrix being the one who teaches Narcisssa Legilimency like after Andromeda leaving since she married a muggle born
9.) Bellatrix felt betrayed when she found out about Andromedas relationship with Ted Tonks and never got over it
10.) Bellatrix and Andromeda hating tea but Narcissa loving it i got this headcannon from that one kardashian meme