She took relative’s horrible offer that's unsolicited (7,8)

I believe the answer is:

hostile takeover

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'offer that's unsolicited' is the definition.
I can't judge whether this definition defines the answer.

'she took relative's horrible' is the wordplay.
'horrible' is an anagram indicator.
'she'+'took'+'relative'='shetookrelative'
'shetookrelative' anagrammed gives 'HOSTILE TAKEOVER'.

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I've seen this clue in The Hindu.

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