Bet on nuns somehow making baby’s hat (9)

I believe the answer is:

sunbonnet

'baby's hat' is the definition.
(hat worn by a baby)

'bet on nuns somehow' is the wordplay.
'somehow' is an anagram indicator.
'bet'+'on'+'nuns'='betonnuns'
'betonnuns' with letters rearranged gives 'SUNBONNET'.

'making' acts as a link.

I've seen this clue in The Times.

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