This is a subtrope of The Smurfette Principle: If she's The Chick in the team, then she's usually someone's sister, girlfriend or love interest. If she's a military or political leader of some sort, then you can bet that she got the position with help from her father or another male relative. The author or the characters have to choose who gets to join in on the hijinks or know the secrets; chances are, most of the people they choose are going to be men. Women who join in are most commonly there as a "bonus" to someone else, often as a love interest or a family member.