Even if you file separate returns, both of you have to indicate the income of your spouse. The family income is then used to calculate credits and deductions. If you do file separately, either of you can claim the children as dependents on your return, as long as each child is claimed only once. If your husband earns much less than you, may be the non-refundable credits would not make a difference in his return if he claims the two youngest or all three.
As you are filing your income tax, TurboTax will offer some tips and advice to get the best return possible.
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