Am I going to get in trouble for my mother giving me money?

I am not really sure of the implications of anything that has happened. Basically 'we' bought a home, only the loan was taken out via family equity scheme, then the repayments were taken from my mothers bank account. So the house was in our names, but when my mother sold her house, it automatically paid out the money that we legally owed. She has always said that half the house is ours and half needs to go to my younger brother (though legally it all belongs to myself and my fiance) and that we would sell the house in a couple of years and give half the money to my brother. THEN she got us to all sign something to say that both myself and my brother owed her money for half of the house each, she said so that legally we got a loan from her, and she did not give us anything and that half of the house should really belong to my brother. Anyway it is all very confusing. What I want to know is if any of us are going to get in any trouble over this, or can parents just give whatever they want to their children?