Please be sure that your dependant's date of birth is not in 2020, as you are doing your 2019 tax return. If you have a baby born in 2020 you will claim them on next year's tax return. CRA will know that you have a child and that will not affect anything. If your child is was born in any other year- please be sure that you entered the date of birth for example- if they were born January 25, 2008, you would enter it as 25/01/2008.
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