Narrated Um Qais bint Mihsin (Radi-Allahu ‘anhum):

I brought my young son, who had not started eating (ordinary food) to Allah’s Apostle (Sallallahu ‘Alaihi Wa Sallam) who took him and made him sit in his lap. The child urinated on the garment of the Prophet (Sallallahu ‘Alaihi Wa Sallam), so he asked for water and poured it over the soiled (area) and did not wash it.

Bukhari Vol. 1 : No. 223