When Neighbor Boy came into our lives--four years ago, if I remember correctly--all the children ran and squealed together; for all intents and purposes, gender differences didn’t exist.  
The three of them were happy to play video games and wield swords in the front yard and chase each other from one house to the other.
But then time moved on and Little Missy’s play time with the boys slowly waned.  
She could no longer feign interest in their video games and would instead color quietly in the other room to bide time until they all went running and squealing outside again.  Then  she stopped going down to Neighbor Boy’s grandparents’ house at all; the boys’ Lego-building, Minecraft world-creating lives ran fully separate from her coloring and reading interests.
And it was very sad.
When Neighbor Boy would knock on the door and G would tear out of the house to hang out with him I’d sometimes prompt Little Missy.  “Don’t you want to go play with the boys, too?”  She’d shrug her shoulders and tilt her head to the side.  “I’m okay!”  But I was sad for her, sad that she’d lost her brother and her friend in one fell swoop that was months in the making.
Then Tuesday night, in the midst of the glorious sunshine that May finally brought, Little Missy and Neighbor Boy ended up playing in the yard together while G was at baseball practice.  Those two dug in the mud, created pathways and dams for the water, then sloshed water in a bucket.  Their mutual love of dirt gave them something to do together.
And it was happy.
The next day before school Little Missy told me that she was going to invite Neighbor Boy over right after school.  And she did.  And the next day it was the same.
And so I am happy for this perfect weather that is conducive to playing outside and getting dirty, giving my daughter her friends back.