This isn't a stealth boast at all I promise!!!
But is it normal for 11 month olds to be able to hum nursery rhymes? I never really took much notice to be honest, but now people are commenting on it in supermarkets etc!
Basically he makes an "eh eh" sound but to the tune of wheels on the bus and twinkle twinkle. I sing to him a lot, so it is really that unusual?!