Penny Pepper-Bean, The Doctor and others in “Dot and Bubble”

We miss you so much, darling. But I'd pay for the whole moon to make you happy. Just look up at the sky and wave to us on the Homeworld. Happy Finetime, Lindy-Loo! And don't forget, you're only a Bubble away.

...who is that?

I told you, it's Mummy.

Hold on, I've seen her before.

Yeah, she's, like, she's the face of the ambulance on Kastarion III.

No, no, no, I've seen her somewhere else...