Faith,
for our case, our angkuku also likes to smile to his granny most, can really use the word beaming smile. I think it's because his granny spent the most time with him. I think I will also smile to the person who clean my poo every now n then.
few weeks ago, I very sian, he smiles only to mummy when we brought him home.
last week, he only smile at me, not to mummy. then mummy very sian.
come next week, maybe he change again and only smile to Cartoon...
the ones on the bumper mat (yes! I got it ytd liao)... hehe..
I think their pattern change very fast...