Crossword Genius

Little child's line on, say, Sweeney TV show (7)

Ross

I believe the answer is:

toddler

'little child's' is the definition.
(a toddler is a young child)

'line on say sweeney tv show' is the wordplay.
'line' becomes 'l' (used when specifying particular lines from a poem).
'on' says to put letters next to each other.
'say sweeney' becomes 'Todd' (Sweeney Todd).
'tv show' becomes 'ER' (US medical drama).
'l' put after 'todd' is 'toddl'.
'toddl'+'er'='TODDLER'

(Other definitions for toddler that I've seen before include "Young child" , "youngster" , "Child starting to walk" , "Young walker" , "One taking first steps" .)

I've seen this clue in The Guardian.
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