Quote from Phoebe in The One with the Cat
Phoebe: I just have this really strong feeling that this cat is my mother. Rachel: The mom you met in Montauk? She was a cat? Phoebe: No. She was a human lady. This is the spirit of my mom, Lily. The one that killed herself. Ross: Are you sure she's in the cat or have you been taking your grandmother's glaucoma medicine again? Phoebe: No, Dr. Skeptismo.