"The Messenger of Allah and I used to perform ablution from a single vessel, when the cat had drunk from it beforehand."
Sunan Ibn Majah Book 1, Hadith 102
← Previous Hadith She poured water for Abu Qatadah to perform ablution. A cat came and drank the water, and he tilted the vessel for it. She started looking at it (in surprise) and he said: "O daughter of my brother, do you find it strange? The Messenger of Allah said: 'They (cats) are not impure, they are of those who go around among you.'"

Sunan Ibn Majah Book 1, Hadith 101 Next Hadith → The Messenger of Allah said: "Cats do not invalidate the prayer, because they are one of the things that are useful in the house."

Sunan Ibn Majah Book 1, Hadith 103