All babies understand language before they can speak. One of the reasons baby sign language works is because it doesn’t require the fine motor control that speaking does, so can be used earlier.

But also, permanent memory develops well after the kid speaks normally, so either he learned to speak later, or he formed that memory unusually soon or he is making things up. I bet three.

you forgot putting "/s" .

I thought it was obvious, but I forgot there are some real geniuses here who can’t tell the difference.