A father has to be male. You cannot be a father without being male. It is not possible to be a father and not be a male. The property of being a sister implies the property of being female and the property of being a sibling.
All sisters are females and they are siblings.
The property of being a female sibling implies the property of being a sister. All female siblings must be sisters. Something is a triangle just in case it is trilateral. Abortion is Murder 2. Abortion is Wrong.