Puppy love, or whatever comes before that

Mason has got his first official crush! He never shares too much info about his school day, (Moooooom, I don't remember!) but all of a sudden he started telling me about this little girl named Elizabeth who is in the preprimary classroom across the hall from him. All of the preprimary classes have recess together, and Mason and Elizabeth play spy games every recess. He occupies the top part of the play structure, she the bottom. They both have "spy assistants" that alert them when the other is coming near or feed them information on each other's location. When I picked him up from school last week I saw her; long blond hair hidden under a mans baseball cap, crouching under the jungle-gym platform and whispering to other children who scurried in and out of her hideout. Mason was running over the wobbly bridge, trying to smoke her out and beaming from ear to ear.
Now after school I get questions that always include "Elizabeth":

"Mom, why does Elizabeth chase me?"
"Can I invite Elizabeth to my birthday party?"
"Does Elizabeth think I look cool?"

and so on and so forth.
awwwww.