For party, for government and for parliament - Rex is bound to be there
I believe the answer is:
doghouse
'government and for parliament rex is bound to be there' is the definition.
I can't tell whether this defines the answer.
'for party' is the wordplay.
'for' becomes 'dog' (I can't explain this - if you can you should give a lot more credence to this answer).
'party' becomes 'house' (house party is a kind of party).
'dog'+'house'='DOGHOUSE'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for doghouse that I've seen before include "Location of disfavour - kennel" , "disgraceful environment" , "Place for one in disfavour" , "where one is in disgrace?" , "Kennel (US)" .)