Things one wants whilst one's sick (4,4)
I believe the answer is:
wish list
'things one wants' is the definition.
(a list of things someone wants to own)
'whilst one's sick' is the wordplay.
I cannot really see how this works, but
'one's' could be 'lis' (I've seen this in other clues) and 'lis' is found within the answer.
This may be the basis of clue (or it may be nonsense).
(Other definitions for wish list that I've seen before include "Enumeration of things desired" , "collection of wanted items" , "Things one would like to have or do" , "Wants" , "Summary of desirable items or actions" .)