Yes you will get it for both of them. If you didn't get a separate check (which you probably didn't didn't since they are born in 2021) you just add them as dependents when you file your 2021 return and the credit will be added on to your return if you qualify if your income isn't too high.
And when you enter them on your tax return be sure to select the WHOLE YEAR for the question How long did the baby live with you if they were born anytime during the year, even in December. You get credit for the whole year.
