After their parents and stepparents passed away, seven siblings must separate differences and work as a family together

Not sure "separate" is the correct word.

A goal is the bare minimum.

The shortest logline I ever heard that won a competition was “A man clones his wife so he can fall in love with her again”

Raise questions. Not really complete. But a clear goal.

To achieve what? Give them an objective goal.

Possible title: Party of Seven