In many adverts, they're paternal (4)
I believe the answer is:
dads
'paternal' is the definition.
The answer and definition are not the same part of speech.
'in many adverts' is the wordplay.
'in many' becomes 'd' (I am not sure about the 'in' bit.).
'adverts' becomes 'ads' ('ad' can be a synonym of 'advert').
'd'+'ads'='DADS'
'they're' acts as a link.
Can you help me to learn more?
(Other definitions for dads that I've seen before include "Fathers, informally" , "Fathers, in short" , "1 across 10" , "Family men" .)