Maybe you missed something when you entered the 7 year old. Try deleting the child and then re-enter her in My Info,
Return to the My Info section to verify what has been entered.
Scroll down to your 7 year old and click the pencil icon to edit. All the questions should be reviewed.
There are questions that sometimes pertain to dependents that alternate from one parent to the other. Perhaps a selection was inadvertently made to exclude the 7 year old.
For more information, see: Rules for Claiming a Dependent on Your Tax Return - TurboTax Tax Tips & Videos