Certain credits are reduced by your dependants' income. For example: For you to claim the eligible dependant credit, the dependant’s earnings must be less than the current year’s Basic Personal Amount (these change yearly, see this CRA link for current year amounts). Your claim will be reduced by the dependant’s earnings so it’s important that if your dependant has any earnings, you complete their tax return first and enter the amount from Line 23600 – Net Income of their tax return on your own return.
For more information, please see our TurboTax article: Claiming the Amount for an Eligible Dependent Credit
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