This person had proven exceedingly irresponsible with money. The donor was worried that he would not be able to keep a roof over his (And his family's) head.

So, while the other children received more liquid assets, this person functionally received a house he could live in. The truth retained ownership. So the IRS and creditors could not come after the house even if they could come after his assets.

As an aside, after the original donor passed away you would not believe (Maybe you would) the amount of grief this individual (And his siblings) gave the executor about giving this person liquid assets in spite of the donor's wishes.