Sleep with relatives of the cloth (6)
I believe the answer is:
napkin
'the cloth' is the definition.
(I've seen this before)
'sleep with relatives' is the wordplay.
'sleep' becomes 'nap' (I've seen this before).
'with' says to put letters next to each other.
'relatives' becomes 'kin' (I've seen this before).
'nap'+'kin'='NAPKIN'
'of' is the link.
(Other definitions for napkin that I've seen before include "Serviette; diaper" , "Protective cloth square worn at meal" , "Cloth square worn while eating" , "piece of material giving consumer protection" , "Cloth square used to protect clothing while eating" .)