Sweden Legalizes Child Marriages For Immigrants
https://dailyeb.com/2017/10/21/sweden-legalizes-child-marriages-for-immigrants/
It's a rare example which shows the phrase "When you are in Roma, do as the Romans do." doesn't work.
I guess it's not good to allow them to marry, because it may cause many contradictions. For example, if a female immigrant bears a child, she or her husband will have to work to feed the child.
But, it would be illegal for them to work ,and it's difficult to change the law, because of Convention on the Rights of the Child.
So, it would be better to define new relationship that restricts some activities allowed in marriage
