Request by mother is material (6)
I believe the answer is:
damask
'is material' is the definition.
(I've seen this before)
'request by mother' is the wordplay.
'request' becomes 'ask' ('ask' can be a synonym of 'request').
'by' means one lot of letters go next to another.
'mother' becomes 'dam' (female parent of an animal).
'ask' put after 'dam' is 'DAMASK'.
(Other definitions for damask that I've seen before include "Lustrous fabric" , "Heavy embroidered linen" , "Lustrous cloth" , "Patterned material" , "Material, originally Syrian" .)