The fate of the recent expansion of the federal child tax credit is uncertain in the ongoing budget negotiations in Congress. What is clear is that poor and low-income families are putting the increased assistance to good use. Nine out of 10 families earning less than $35,000 are spending the money on one or more essential living expenses, which include food, utilities, housing, clothing or education needs like books and after-school programs, according to an analysis of U.S. Census data by the Center on Budget and Policy Priorities. The American Rescue Plan passed in March temporarily increased the credit from $2,000 to $3,600 per year per child for kids under age 6 and to $3,000 for older kids and teenagers…