So your saying, for example, your husbands brothers kids, ie your sisters new nieces / nephews, become your kids cousins
No they don't, any children you have are cousins of your sisters children yes, but your husbands siblings kids are not cousins of your kids, only your sisters - very confusing, thank f**k my family keep themselves to themselves, as that is tooooo confusing for an adult let alone kids!!!
Its like those families that have "aunties", that turn out ot be friends of the family
The wedding day is a joining of 2 people, through love, and if they decide such, to go on and create their own family, family are merely there to witness the event and to pay their respects to the relationship, not run the show