Who kept the money is probative, not dispositive.  What if father wrote daughter a check for $200,000 the same day he deeded son the real estate worth $200,000 after taxes?  What if he had been making such gifts every year for the last five years?  What if father lived with son, benefited from his large household staff and could drive the Lamborghini on weekends?  If this were a salary bonus, "assignment of income" wouldn't care who cashed the check or kept the funds.  It's somewhat more complicated when property is involved -- you have to look at all the facts and circumstances.