cats have a saint

They surely do: St. Gertrude of Nivelles, born 626 in Belgium, died 659 in Nivelles, in the convent where she had been abbess since age 20.

She's also the patroness of travelers in search of lodging, gardeners and herbalists, and those that have recently died. She is often depicted with mice running up a staff that she holds. This is because she is invoked against mice, of course, being the patroness of cats. But part of her iconography (the practice of recognizing symbols for ideas in art) sees the mice as representative of souls that are newly dead. A popular belief in Gertrude's time and years after held that souls went on a three-day journey to the next life, and that the first night of this journey was spent specially under Gertrude's care.

Learn about Gertrude here (a very pretty site) and here.