But if Sir T hadn't sold the living, Edmund woudln't need better preferment! and selling up, say the Antigua property would problaby realise a good sum of money. However I agree that we dont know how the proprerty is settled and it may be that the living is the only peice of property Sir T can sell.

But I think that the fact that he realises its an injustice makes it rather worse. A lot of fathers would just accpet that a lad like TOm woudl be extravagant and run uup debts and tehy woudl just live iwth the debt.. and if they had to sell a younger son's living they woudl do so in the spirit that "yes its a bit hard on Edmund but after all the estate is the most important thing and the elder son is more important than the younger one.."..But Sir T has in his way an idea of fairness, that is a little in advance of its time... I dont expect him to go mad and try and split the estate between all the children or campaign for votes for women. But within the limits of his way of thinking, I think if he can see the injustice of depriving Edmund of his income, why not then do his best to make hte punishment fall more on Tom? Send him off to Antigua to run the estate there and say "make it pay" or jsut let the debts be a charge on the estate so that in the end they'll fall on Tom's head, and that may force him to grow up and be more responsible once he inherits?
I agree that we dont know exactly what Tom's income is, but I think that if Austen had intended Tom to have some money of his own she could have siad so in a sentence.. such as "Tom had a small property of his own from his godfather but it had proved insufficient to his needs".....So I think we can fairly assueme that he's living on an allowance from his father and has nothing else...Ed Ferrars was in a differnt sitution, in that I imagine HIS fahter left him a small independence, but left the bulk of his estate to his wife and expected that Edward would inherit it all in time...
I think that given Tom's spoilt selfish way of going on, we can assume that whatever Sir T has doen (if anything) to try and make him shape up has not been enough, and he's pretty hard to reach... Probably nothing but "illness and disaster" COULD reform him, but I think that Sir T is to blame a bit for letting him get that way....