Liam often has his eye on Brian, but I don't think it is jealousy over his personality, after all... Brian doesn't actually have a personality - he has ten! They change all the time. Don't get me wrong, I like that he has been clever enough to watch every single episode of every single Big Brother and take a part of each successful character, then merge them all into one, i.e. "Brian." But I would love to see the real Brian, not this made up act.
As for Liam, he is clearly interested in Amanda and watches her and Brian in an attempt to suss them out. I think this is where you have assmed he is jealous of Brian. More likely story is he is sneakily watching his competition for the girl.
Liam is bloody lovely, he has such a dry sense of humour - typical northern lad! Liam to win! That would be class - him taking all the money!!!