Whistler's Mother couldn't exist without them to lubricate Father in discontented times (3,6)
I believe the answer is:
oil paints
'whistler's mother couldn't exist without them' is the definition.
I can't tell whether this definition defines the answer.
'lubricate father in discontented times' is the wordplay.
'lubricate' becomes 'oil' (synonyms).
'father' becomes 'pa' (pa can mean dad or father).
'discontented' means to remove the middle letters (the word\'s contents are removed).
'times' with its centre removed is 'ts'.
'oil'+'pa'+'in'+'ts'='OIL PAINTS'
'to' acts as a link.
Can you help me to learn more?
(Other definitions for oil paints that I've seen before include "Painter's media" , "What some artists use" , "Artist's pigments" , "Artist materials" .)