Kitty showing faith and amusement, on the day (5,4)

I believe the answer is:
trust fund
'kitty' is the definition.
The answer and definition can be both related to property as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'faith and amusement on the day' is the wordplay.
'faith' becomes 'trust' (synonyms).
'and' says to put letters next to each other.
'amusement' becomes 'fun' (I've seen this before).
'on' says to put letters next to each other (in a down clue, letters appear on others).
'the day' becomes 'd' (abbreviation for day).
'trust'+'fun'+'d'='TRUST FUND'
'showing' is the link.
Can you help me to learn more?
(Other definitions for trust fund that I've seen before include "Assets held for the good of beneficiaries" , "Reserved money" , "This money's set aside" , "In which money may be held" .)
