Yes it should be added to your tax return.
Go back to My Info and make sure you said your baby lived with you the WHOLE YEAR and not just the number of months. Even a baby was born on Dec 31 is considered to live with you the whole year. You might have to delete the baby and re add him. Pay attention to the questions, especially the one asking if he paid more than half of his support.
Then at the end you enter the amounts you already got and if you qualify for more it will be added to 1040 line 30.
