When Libby saw Crystal...
What was going on with her reaction? Did she have a moment of clarity regarding the nights events?
Was she overwhelmed finding out about and seeing her niece for the first time?
The way the scenes are cut I thought she was just struck by Crystal's resemblance to her sister but Crystal is supposed to be 28 / 29 and is only comparable to a young teen girl because a damn stupid casting choice (don't pick an actress younger than the role if she already looks young for her age, and then compound the issue by dressing her like a teenager).
I get that Crystal is supposed to be a pampered mentally deranged princess, and this effect would have been bolstered by choosing an actress who looked like a 30 year old dressing and acting as a teenager, not the opposite.