Taking a gift from someone who's wealth is doubtful

A friend of ours is unemployed and dependent financially on the government but is actively looking for work. He has a mother who repeatedly tells him that she will buy him a house, which gives him hope because he can live on the rental yields and not be in fear of eviction while he continues to search for a job. He will also be in a better position to transfer his mother's house to his name so as to avoid inheritance tax. The problem is that her wealth is very dubious and most likely gained in a haram way. For some time now she has been receiving benefits from the government but recently she has also been renting out rooms in her house. How she amassed her wealth is another story and cannot be explained by the benefits she receives but from what things she did (and probably still does) like take interest from the banks, working in betting establishments, and committing refund fraud. My questions are:

Can he receive a gift from his mother?

Can he inherit from her?