I am so sorry about your daughter. I want to tell you that again.

In regards to cats...I think they vary. We have one cat that grieves alot all the time, when my husband is not with her during vacation interruptions. We all go up north together and he comes home to work some, and then returns.
She is very attached to him, and her behavior changes when he leaves.
She was also very upset when a young male cat we used to have, was killed
suddenly. She was depressed for several weeks. We finally got her a kitten companion. (they play together now).
Our other cat could care less. So it can be very individual. (cats can be very strange sometimes--eccentric).

If you can get their bowls, and use them at your house, that might help with
the transition.
Also some clothing of your daughter's that still has her scent on them (unwashed--like robes, sweaters).
The cats' pillows, blankets etc. This might be hard for YOU, to see the articles around your house, but it might really help THEM.

Cats are very flexible however. My son has an adopted female rescue adult, who bonded very well with both he and his roommate. He has had her over a year, and she became acutely ill and he had to leave her at the Vet's for a weekend on IVs and she went bonkers, thinking she was abandoned again. This was an unexpected clue into her psyche...he did not think she "cared" that much.

Cats are all very different however. I'd give at least 2 weeks, and maybe longer for the fearful one. Some extra attention in the way of food treats, helps. Did your daughter give special food treats? Like chicken, shrimp (we do this) or other goodies? If not, you could start a new tradition, and cats really groove on FOOD..more than you would think! (we give a food treat only once a day..a special attention time).