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Given that the family will include a child it is impossible for a possible para 6A problem to arise. So yes, as soon as the family are here he should indeed claim Housing Benefit and Council Tax Benefit. But also, as soon as the wife has moved in, he needs to notify the Council that he is no longer entitled to the single occupant discount.Do you also know about housing benefit I know that he will be allowed to claim it once his wife and child are over here but I am not sure if this will affect her ILR.
You really do need to download the form SET(M) and read what it says about documentary evidence to be supplied with the completed form.we dont have any bill on our name