Pot knocked over: relatives will get serviette (6)
I believe the answer is:
napkin
'serviette' is the definition.
('napkin' can be a synonym of 'serviette')
'pot knocked over relatives' is the wordplay.
'pot' becomes 'pan' (I've seen this before).
'knocked over' says the letters should be written in reverse.
'relatives' becomes 'kin' (I've seen this before).
'pan' written backwards gives 'nap'.
'nap'+'kin'='NAPKIN'
'will get' is the link.
(Other definitions for napkin that I've seen before include "piece of material giving consumer protection" , "Cloth for wiping" , "Cloth rectangle worn at mealtime" , "Cloth to stop, eg, gravy" , "Diner's cloth" .)