They know how to listen

“Men with sisters tend to be better listeners,” says Murray. “By and large, women use more words than men do. If you’re around people who talk more, then you’re exposed to a lot more words. But boys, as a consequence, may not express themselves so much through words, but through behavior and their physicality.

“Words are less relied upon to communicate with other boys. When you have a mixed-gender household, you’re fusing these two strategies together. As a result, boys with sisters are exposed to more words and are more likely to be good listeners.”

They understand we are human

As women we are often made to feel like we have to be superhuman; meaning we don’t show traits of being a living, breathing thing — lest we become entirely unappealing and borderline gross.

I’ll give you two examples: One boyfriend, who had an older brother, made it clear early on that he was wildly turned off by women who alluded to the fact that they had to use the bathroom. Apparently women have this magic ability to wish away any aftereffects of a night of cheap beer and chicken wings with their boyfriends, so that we are powder fresh 100% of the time. I was not aware I possessed this power, but I learned real fast. It was a long, long four years.

Another choice example: One man, one of four brothers, (in his mid-30s, mind you) asked me if and when “Aunt Flo” was still in town. I didn’t know good ol’ Aunt Flo hung around after middle school, let alone into our 30s. It’s also not my “friend” or “that time of the month.” It’s a period. Period.

“Men who grow up with sisters aren’t as freaked out by ‘girl stuff’ because they got exposed to it early on,” says Anderson. “Like periods. They’ve seen a tampon. It’s not so much of a mystery. In that way, women can relate more comfortably because they don’t feel like they are an alien or a foreign being. It helps narrow the gap in terms of wondering. Having no direct contact with an age-appropriate woman in your house tends to make men less comfortable around ‘girly’ things.”

They know how to compromise

“When you have a brother-and-sister dynamic you have to learn how to compromise,” says Murray. “And so you’re more likely to have a feminist among men who have sisters, than I imagine you would among men who don’t.”

They have seen us go through it all

“Depending on whether or not a boy was an older or younger brother to a sister will change his reaction to watching her go through a bad breakup,” says Murray. “An older brother might think, ‘I need to kick the shit out of that guy,’ in a hyper-masculine response. Whereas a younger brother might be more intuitive, more sensitive, more interested, and more engaged. He might be trying to understand what it is like for you, as a female in relationships, so that he’s better able to find a mate.”

Granted, this doesn’t mean every good man grew up alongside a sister. Like any science, there are exceptions to the rule — and it’s unfair to assume all men raised without sisters make crappy partners. Parents, friends, and other non-sisterly influencers can do a lot to ready young boys to coexist with this new generation of smart, strong, independent women.

“I intentionally talk to my boys about ‘girly’ stuff because I’m determined to raise emotionally intelligent boys,” Anderson says. “I told my 11-year-old what menstruation is. And sure, he gets grossed out, but he asks all the questions. I want them to be adjusted.”

My exes are (with rare exception) by no means bad men. In fact, most of them are really great. But should you be wondering whether that sweet guy you just met has what it takes to stick with you for the long haul, you might want to ask about his background. And specifically, his siblings. If he’s proud to tell you about the pack of sisters who raised him, odds are good you’ve found yourself a prince.