Gamora & Nebula
According to the Merriam-Webster Dictionary, the definition of 'sister' is:
sis·ter | \ ˈsi-stər \ noun
1: a female who has one or both parents in common with another 2: often capitalized a: a member of a women's religious order (as of nuns or deaconesses) especially : one of a Roman Catholic congregation under simple vows b: a girl or woman who is a member of a Christian church 3. a: a girl or woman regarded as a comrade b: a girl or woman who shares with another a common national or racial origin especially : a black girl or woman 4: one that is closely similar to or associated with another sister cities 5chiefly British : NURSE 6. a: GIRL, WOMAN b: PERSON —usually used in the phrase weak sister 7: a member of a sorority
Then I did a search for what sisters do, and one woman, who lost her sister nine years ago, wrote the following list:
18 Things All Sisters Should Do Together Before They Turn 18
Sisters have a special brand of magic. Here are 18 things to do with your sister before you turn 18 to honor that sister magic. And if you’re an adult with a sister and you haven’t checked off all these awesome sister-bonding activities quite yet, I promise you it’s not too late.
1. Stay up late in bed together, whispering made up stories to each other. 2. Try out new hairstyles on each other. (As long as no scissors are involved.) 3. Sneak the younger one into a movie she’s technically too young for. 4. Have a knock-down-drag-out fight over something stupid. Then apologize to each other, without anyone forcing you to. 5. Admit your deepest, darkest fears to each other – whether she’s afraid her nose is too big for her face or you’re afraid you’ll never understand chemistry. 6. Borrow each other’s clothes or jewelry. 7. Do a 1000-piece puzzle together. 8. Share inside jokes that no one else understands. 9. Bake something together and get batter everywhere, even the ceiling. 10. Hear a new song on the radio, fall in love with it, and go on an all-day binge listening to all that artist’s music. 11. Play a prank on your parents. 12. Teach the younger one what to do if someone touches your body in a way you don’t like. 13. Give yourselves matching pedicures. 14. Spend all day in your jammies watching your favorite movies. 15. Ride a scary roller coaster together. 16. Read out loud to each other. 17. Go to each other’s sports games, concerts, and plays. 18. When she’s fighting with her friends, listen and take her side – because she’ll return the favor one day.