Add ... Small child out of bed (3,2)

I believe the answer is:

tot up

'add' is the definition.
(synonyms)

'small child out of bed' is the wordplay.
'small child' becomes 'tot' (tot can mean a baby or toddler).
'out of bed' becomes 'up' (synonyms).
'tot'+'up'='TOT UP'

(Other definitions for tot up that I've seen before include "Add together (driving offences)" , "Summate" , "Add (some numbers)" , "Determine the sum of" , "Count" .)

I've seen this clue in the Sydney Morning Herald.

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