You receive a text from a friend to invite you over for diner. Is it ok to ask whether you can bring an extra guest? It is an adult that is currently living at your place. Not friend with people hosting but they have met him before.
I should add that the same question had already been asked for a prior diner at same friends' place and they declined as they were at max catering capacity.
ETA It's not a family friend more like a house-share mate, he is visiting Australia for 3 months and renting a bedroom.