Помогите пжлста решить 27 задачу

1 уровень - country, family
2 уровень - syster, brother
3 уровень - нет

familymother.txt
familyfather.txt
familysystermary.txt
familysysterkate.txt
familybrotherpeter.txt
familybrotherrobert.txt
familybrothermikle.txt

Спасибо)