its hard to say. my fd's 30 mths old is over 1 meter tall and 18kg already. he definitely looks 4 to 5 easily but he is really still a baby. u cant expect his mom to hold him when he naps. but then if he is napping in the stroller ppl like urself will judge her and question her. so I would say it's nobody's business but their own. there might be reasons underneath all these.