After calling Alex (she yells at him while she gets
dressed, occasionally necessitating slightly hilarious breaks in her tirade while she puts it down to do up a zipper with both hands), Jemima assures her father that she knew Cally was coming and that it just slipped her mind to point it out. (Martel looks skeptical, but this is admittedly relatively tame compared to the things she could be springing on him with her little troupe of madmen, so he tells her to leave her cellphone on and doesn't protest when she grabs her carkeys and runs down the stairs.
By the time she gets to the Hilton, she's still not totally sold on Alex's excuse- but at least the whole mess doesn't seem to be Cally's fault, so she resolves to put her best foot forward and take care of things anyway. It is, after all, kind of what she does. (A sister! A sister she had no idea existed! How did she miss that? He is so lucky he's not in New York.)
Jemima requests that the desk let Cally know she's here, and waits.