It was narrated from `Ali bin Abi Talib (رضي الله عنه) that The Messenger of Allah (ﷺ) said concerning the nursing infant: `Sprinkle water on the urine of a boy and wash the urine of a girl.` Qatadah said: This applies so long as they are not eating solid food; if they are eating solid food, then it is to be washed in both cases.