My wife and I have two children who live with us. One is ours (9 months old) and one is my wife's from a previous marriage (6 years old). Per the divorce agreement, it is our year to claim the 6 year old as a dependent for tax purposes. It is my understanding that we should receive a $2000 tax credit per qualifying dependent child, or $4000 total. TurboTax, however, credits us $2000 for our baby, but only $500 for our 6 year old. TurboTax tells us each child qualifies as a "dependent," but says our 6 year old is "disqualified" from the $2000 Child Tax Credit without telling us why. Instead, TurboTax says he qualifies for the "Credit for Other Dependents, which is capped at $500. Even when say that my wife and I are the 6 year old's legal parents, the result is the same. Why
suggest going through this IRS website and answering the questions - it will explain what is occurring in about 5 minutes!
Is it possible you are answering one of the questions incorrectly as Turbo Tax mimics these IRS requirements? I tested this in my TT Deluxe Desktop version and it provided the $2000 credit for the step-child so i suspect it's the way you answered one of the questions.
the child has an SS# and you and your wife are filing joint? did you recheck the birth date (if you mistyped and shows child is over 16, that could be a reason) ?
did you answer that the child is your wife's child and that should have caused TT to ask questions about custody agreements which is where you'd reflect it's your year to take the credit. did you answer that the biological father is not taking the credit this year Ithat is a question)
Try deleting the six-year-old and re-entering his information in TurboTax. It sounds like you should be able to claim both children as qualifying child dependents eligible for the $2000 credit. Sometimes you need to clear out information that was previously entered and start fresh with that dependent.