Tic-Tac-Toe

Today I was watching Sadie play outside with some neighborhood kids. They were playing with sidewalk chalk. And I think at some point Sadie learned to play tic-tac-toe. Some of the kids left, so it was down to Sadie and one other girl who is 5. Sadie drew a tic-tac-toe game and asked her if she would play with her. The girl ignored her. Sadie asked again. More ignoring. I was getting a little annoyed with the girl, but decided not to intervene . . . maybe she just doesn't want to play. I think Sadie kind of gave up at this point, but then a little boy was riding by on his bike and the little girl asked him, "Do you want to play with me?" He did. Then this girl asked, "Do you want to play tic-tac-toe?" I couldn't believe it. Here she was ignoring my sweet little girl, but she will play with someone else.

These kids began to play and Sadie tried to join. Here's what I could hear:
"Could I play?"
No response.
"Hey, can I play?"
Still no response.
"Your not letting me play" (she had been waiting her turn)
"This for two people"
"I really want to play"
The kids run off.

I offered to play with Sadie, but the damage had been done. I don't understand how kids who are this young can me so mean. This is the weird thing: Sadie and this girl had a lot of fun together at the beginning of the summer, so I don't understand why she is just totally being mean now. I wanted to go and MAKE that girl play with my daughter and like it. She has no right to ignore my sweet angel, especially when she was being so mature about asking to play.

Anyway, Sadie and I played for awhile, but it ended up as an enormous fit with pee all over our carpet. Why are girls so emotional?