Team up with the children and take part in the controversy (4,5)

I believe the answer is:

join issue

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'take part in the controversy' is the definition.
I know nothing about this answer so I can't judge whether it can be defined by this definition.

'team up with the children' is the wordplay.
'team up with' becomes 'join' (I've seen this in another clue).
'the children' becomes 'issue' (issue can mean someone's offspring).
'join'+'issue'='JOIN ISSUE'

'and' acts as a link.

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I've seen this clue in the Evening Standard.

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