Do I check that my son received income as he received CERB as a student. He is dependent on me and I have paid all his tuition fees etc.

Yes, you should include that your son has received income, despite it being CERB. Although, his income may affect the credit amount you may receive from the dependant tax credit if it is applicable to you. if you'd like to know more about what family deductions you may claim, here is a great TurboTax article. 

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