My relatives are abusing my nephew's trust fund. Morgan Stanley handles the trust but my relatives lie to them?

[aescby]

My great nephew received a very large trust in a wrongful death lawsuit. He is only 15 so Morgan Stanley manages the trust. My sister and her family have gone crazy with his money. They bought a big new house and receive a monthly draw for living expenses from his trust fund. That is all fine but the problem is that only my sister, my brother-in-law and my nephew are supposed to reside in the home, however, now my 26 year old nephew, his wife, their new baby AND my unemployed 30 year old neice and her unemployed boyfriend have all moved into the house. Of those extra 5 people, only my nephew works. Only my sister, brother-in-law and great nephew are suppossed to live in the home. They have not disclosed any of this to Morgan Stanley. In fact, they are hiding this from them!. What should I do?