I know I would do everything in my power to help my own children and particularly in the circumstances you have explained, however, my view is that for your daughter and her son to move in with you and your husband is a step too far. It is bound to lead to tension if your husband is opposed, no matter whether his reasons are good or bad - and this wont be nice for your grandson, daughter or you. I would offer every kind of help possible, financial, help with food, childcare etc. but not moving in unless it was a clearly time-limited stop-gap with a mutually agreed end date for all concerned.
Our Welfare State. Is it broken?
The Republic of Ireland and their tensions with migrants.