With all due respect, please not a cat. For some reason, it's become the symbol of single women in comics - Supergirl had a cat, Power Girl had a cat, Captain Marvel had a cat (okay, a flerkin, but before that writer, it was a cat ), and in the pilot for the WW TV show a few years back, Diana had a cat.
Men get dogs, women get cats just doesn't work for me.
I'm all for Cerberus' offspring.