Brandon's "Stages of Friendship"

Brandon has a new friend, Naruyuki, who he really likes at school. He and I met his family at the park last Sunday so that they could play together, they get along really well. Naruyuki's Mom is Japanese and his Dad is Italian.

We were talking last night about seeing if they are free for a playdate on Saturday. Brandon started said something like, "Maybe someday we can have a sleepover, but we aren't to that stage yet." He then proceeded to tell us the stages of friendship:
1. Play date at the park
2. Play date at your house for a couple of hours
3. Come over for lunch
4. Come over for dinner
5. Sleep over

We jokingly added Step 6: Visit each other in Oregon or Japan.

Where does he come up with this stuff? He even mentioned it again this morning, something about "we aren't to that stage yet...", I don't even know what he was talking about.

I wonder what detailed process and stages he will come up with once he starts dating!!