Cat (The Empty Child)

A stray cat was lying on in a wooden crate in a London alleyway within which the TARDIS had materialised earlier. The Ninth Doctor then picked them up, and told them that "one day [he's] gonna meet somebody who gets the whole "don't wander off" thing", and commented "900 years of phone-box travel, it's the only thing left to surprise [him]!" and petted them before the TARDIS telephone went off - something that the Doctor claimed should have been impossible as the phone wasn't real - and he put them back down on the crate so he could investigate. (TV: The Empty Child)