Wets a nightgown, knocking some over, so they're having problems (2,1,4)
I believe the answer is:
in a stew
'nightgown knocking some over so they're having problems' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'wets a' is the wordplay.
I cannot really understand how this works, but
an anagram of 'wets' is 'stew' which is within the answer.
'a' is found in the answer.
The remaining letters 'in' is a valid word which might be clued in a way I don't see.
This may be the basis of the clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for in a stew that I've seen before include "In a state of great agitation - simmering in pot?" , "Very worried" .)