Seal acted oddly and grew (9)

I believe the answer is:

escalated

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'grew' is the definition.
The definition and answer can be both related to change as well as being past participle verbs.
Maybe you can see an association between them that I don't see?

'seal acted oddly' is the wordplay.
'oddly' is an anagram indicator (letters in an odd order).
'seal'+'acted'='sealacted'
'sealacted' with letters rearranged gives 'ESCALATED'.

'and' is the link.

Can you help me to learn more?

I've seen this clue in The Daily Express.

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