Fill up the ward (6)

I believe the answer is:

charge

I believe this clue is a double definition.

'fill up' is the first definition.
(I know that charge is a more specific form of fill up)

'ward' is the second definition.
(both can mean a child in someone's care)

'the' acts as a link.

(Other definitions for charge that I've seen before include "Fill; fee" , "person in custody" , "Race to attack" , "Keeping" , "Accuse; load, fill" .)

I've seen this clue in the Evening Standard.

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