Is it true that my stepdaughters are not eligible to be claimed as dependents?
Not exactly. If they did not have their SSNs by the due date of your tax return, you can claim them as "other dependents" for a $500 credit, but you can't get the $2000 child tax credit or earned income credit, even if you file an amended return after the SSN is awarded.
Unfortunately, if you had requested an extension, your due date would have been October 15, 2023, and your return would have been "on time" if you waited until the SSNs were issued in May. It's too late for you, sorry to say, but this information may help someone else in the future.
