Ay, 20 kilos sa 18 months is quite heavy talaga, lalo na kung mostly rice and milk lang ang kain niya, I'd really suggest bringing her to your pedia para ma-check kung okay lang siya or if need ng adjustments sa diet, kasi sometimes ang rapid weight gain can signal something na kailangan i-monitor. A few of us mums noticed na pag sobrang dami ng rice and milk without other nutrients, ang babies tend to gain pero hindi healthy yung gain, so better safe na mag-check with the doctor na lang para ma-guide kayo properly.