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Love Live!
Characters - Family Members
Alisa is Eli's younger sister who is a big fan of μ's. She attends the same junior high school as her friend, Yukiho.
Yukiho is Honoka's younger sister who lives in the back of the family store along with the rest of the family.
Kotori's mother is the principal of Otonokizaka Academy. She didn't seem to be as upset by its impending closure as her daughter was.
Maki's mother is the administrator of a hospital who expects Maki to eventually take over the role. She seems to be a long time friend of Kotori's mother.
Honoka's mother runs the family-owned Japanese sweets shop along with her husband, who is rather the strong, silent type.
Nico's mother is a busy career woman who is seldom home, leaving the care of her younger children to Nico.
Cocoro seems to be the eldest of Nico's younger siblings. She's rather precocious, but still believes everything her older sis tells her.
Kotaro is the youngest yazawa sibling who always has snot hanging off his nose, while Cocoa seems to be a rambunctious but happy child.
I've kept the descriptions short to limit the amount of spoilers.
Some personal theories regarding characters and family members can be found at Love Live! School Idol Headcanons. (I really liked the one about Nico's mother and "Nico-Ni"... I think it's very interesting and made a lot of sense!)