I hv a fren Preg 4mth no morning sickness at all issit normal?

A fren of mine, preg for 4mth but no morning sickness and no sign of pregnancy at all (belly looks flat) but she went to gynae confirm she is preg...also she always eat 2 spoonful of rice , i feel pity for her baby..my fren scare eat too much later big fat baby cannot deliver at the later stage.. also she told us she wan to maintain her slim waist...lol