Why was my dependant credit not included in my federal return

It depends.

To qualify for the child tax credit, your child must meet the following requirements: 

1. Be under the age of 17 at the end of the year 
2. Son, daughter, stepchild, sibling 
3. Have a social security number 
4. Lived with you for more than half the year 
5. Didn't pay more than half of their expenses during the year 
6. US citizen, US National, or US resident alien 

Child Tax Credit requirements 

TurboTax determines the status of your dependent based upon the answers you provide as you go through the question. 

I recommend you go back into the My info section of the return.  You can find this on the left black panel. 

Select your dependent below your information and review your answers to all of the questions.   

TurboTax will update the status as a qualifying child if they meet all of the requirements as outlined in the attached article. 

Child Tax Credit requirements 

Qualifying child or relative requirements