New Tax Law Question

From

Under the new Tax Cuts and Jobs Act (TCJA) the following child tax credit changes will take place in 2018:

The Child Tax Credit under 2018 tax reform is worth up to $2,000 per qualifying child. The age cut-off remains at 17 (the child must be under

17 at the end of the year for taxpayers to claim the credit). The refundable portion of the credit is limited to $1,400. This amount will be adjusted for inflation after 2018. The earned income threshold for the refundable credit is lowered to $2,500. The beginning credit phaseout for the CTC increases to $200,000 ($400,000 for joint filers). The phaseout also applies to the new family tax credit. The child must have a valid SSN to claim the nonrefundable and refundable credit.