Retirement tax questions

You have been very helpful, and thank you for that.  I do have one more question about federal returns.  My husband has power of attorney for his uncle, and handles his investments.  He is listed jointly on one  managed portfolio mutual funds, non IRA.  He does not receive any income for this; it is strictly his uncle.  Is my husband required to declare it on our tax return?  His uncle will declare it on his own return.