Sarah's there. Somehow. Of course she's there. This is the Doctor's party, after all.

And we all know how much Sarah cares for the Doctor. Unless this is Milliways!Sarah, but it isn't, so...

She has a gift: a small potted bush of daisies. What? It's as good a gift as any -- daisies make the perfect travelling companion. They listen, they don't run off, and they are, of course, rather pretty to look at.