If my spouse owe back child support with fro (family responsibilities office) will cra/fro take my refund and tax credits too if we file common law?

[TurboTaxBrenda1]

Regardless of the situation they can only take from who owes. Even if you do a coupled return you both will end up with either an amount owing or refund at the end. From there if there any funds owing CRA will allocate accordingly.