Musnad Ahmad 2732

It was narrated that Ibn ‘Abbas (رضي الله عنه) said: Ummul-Fadl, the daughter of al-Harith brought Umm Habeebah bint 'Abbas and put her in the lap of the Messenger of Allah (ﷺ), and she (the child) urinated. Ummul-Fadl snatched her up and smacked her between her shoulders, then she took her away. The Messenger of Allah (ﷺ) said: "Give me a cup of water." And he poured it over the spot where she had urinated, then he said: "Pour water over the urine (on the ground).”