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Original Description:
 
Spoiled Rich, Cookie Crumbles, and Nurse Sweetheart are sisters! Previously named Spoiled Milk until she married Filthy Rich, Spoiled Rich is the oldest of the three mares and looks down on her two younger sisters. She thinks Cookie Crumbles has settled for a mediocre life with a mediocre husband, and that her youngest sister could focus more on marrying into a good life instead wasting her time working herself ragged at the hospital and giving any extra attention to her oddball daughter.
 
Nurse Sweetheart, originally called Ice Lolly, is not interested in a relationship with Spoiled Rich or any stallion she tries to recommend to prove she’s in the wealthy inner circle. Sweetheart just wants to prioritize her career and daughter, and doesn’t want to even think about being in another romantic relationship. She politely but firmly ignores her oldest sister, who loves to brag about her life whenever she spots Sweetheart in Ponyville.
 
Cookie Crumbles, on the other hand, just wants the three to be as close as they were as fillies. She does her best to be the mediator of the two, and spends time with both sisters in hopes that she’ll eventually be able to bring them back together. Cookie sees nothing wrong with either of their lifestyles, and makes excuses for most of Spoiled Rich’s rude comments about her life, marriage, and children, claiming her sister is just trying to help in the way she knows how: nagging.  
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These three being sisters means that Diamond Tiara, Rarity, Sweetie Belle, and Screwball are all cousins! They barely spent time together growing up, simply because of the lack of bond between each of them.