DYS10 had finished his piano lesson and we were waiting on his sister, when a girl came in for a make-up lesson. She sat down and started sketching. My son was quietly talking to himself and I wasn't paying attention.

The girl looks up from her sketch pad and starts saying the same numbers as my son, in unison. When they finish, she says, "I like Pi." He says, "I do too. Let's start again." The girl got to 30 digits and my son 45. Then they happily chatted away until it was time to go.

It always makes me so happy when my son meets someone who appreciates his quirks.