Sister...I'm sorry (Mamamoo)

Episode

용선

The eldest of four siblings. 22 years old

별이

She is a twin among four siblings, but the second one is 16 years old.

석진

The third of four siblings is a twin, but is 16 years old.

휘인

The youngest of four siblings, 14 years old

하니

Star's best friend

혜진

Wheein's best friend