Parties essentially bother child: it's rejecting all outsiders, fully (2,3,4)

I believe the answer is:
to the hilt
'fully' is the definition.
(thesaurus)
'parties essentially bother child it's rejecting all outsiders' is the wordplay.
I cannot really see how this works, but
'child' could be 'tot' (term for a young child) and 'tot' is located in the answer.
'it' could be 't' (abbreviation. e.g. in 'tis) and 't' is present in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for to the hilt that I've seen before include "Completely" , "as much as possible" .)
