State Residency for Military Dependent Child requiring individual return due to 1099-B sales

The provisions of the Service Relief Act (military members) and Military Spouse Relief Act (military spouse) do not apply to your dependent children.  They must file in the state they reside since they have a tax filing requirement. 

In the "My Info" section since you are claiming the income on your return you will select that you have income from another state.  That will generate the return for the state you reside in.  You will enter everything in the federal interview as normal claiming the child's income on your return. 

Complete the non-resident state interview ensuring only the child's income is allocated there.  Take note of the income and the tax on the income in that state.  You will use those numbers to claim a credit for taxes paid to another state on your resident return.  

Your child's income should be included/taxed on your resident return, but again you should claim a credit to mitigate that double taxation.

The other option is to complete a separate federal return with only your child's income and indicate the child is a resident of the state you reside in. That will generate the state return with only your child's income instead of having the income on your returns.