Most lucky mother’s self-introduction, returning to be hugged by kid (8)
I believe the answer is:
jammiest
'most lucky' is the definition.
(jammy can mean lucky in an annoying way)
'returning to be hugged by kid' is the wordplay.
'returning' becomes 'mi' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'to' is a charade indicator (letters next to each other) (I've seen this in other clues).
'be' becomes 'am'.
'hugged by' indicates putting letters inside (I've seen this in other clues).
'kid' becomes 'jest' (both can mean to joke).
'mi' after 'am' is 'ammi'.
'ammi' going within 'jest' is 'JAMMIEST'.
'mother's self-introduction' acts as a link.
I am not very happy about this link. Some or all of it may belong to another bit of the clue.