From MegKF:

The daughter of a washed out actress is given the chance to see what it's like to be in a real family.

Itsumi's mother, Kei, is a washed-up actress. One day, Itsumi meets a lady with a severe heart condition and receives an invitation to her house. The house, which Itsumi thinks of as the ideal family home, was just a performance arranged for the lady. Among the family members, Itsumi meets Shuu, a very polite boy, and is persuaded to play in a theatre… ?!