Why is my return under REVIEW STATUS WHEN THEY HAVE ALREADY SENT ME REFUND LAST YEAR WITH THE SAME DEPEDENTS AND CHIld credir

TurboTax never knows when or why the IRS puts a return under review.   Sometimes that is a random action for the IRS; sometimes there is an anomaly that brings your return under review.   All you can do is be patient and provide the IRS with any information if they ask for it.  

Did you claim  a Recovery Rebate Credit?  The IRS is validating those returns.