The idiot dumping child for her (5)

I believe the answer is:

heidi

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'her' is the definition.

'the idiot dumping child' is the wordplay.
'HEIDI' is hidden within the letters.
But, I am uncertain how this is indicated.

'for' is the link.

Can you help me to learn more?

(Other definitions for heidi that I've seen before include "German lady's name" , "lady - from Cologne?" , "Girl's name (from German)" , "Novel Swiss girl" , "book" .)

I've seen this clue in The Guardian.

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