Legal Question in Family Law in Connecticut

It's not illegal. Of course, a lot of other factors might indicate that it is or isn't a good idea, like: are they brother and sister? how much older than 6? If the question is: Mom (or Dad) has a 2 bedroom unit. When she (or he) has weekend visitation, is it OK for the 2 kids to share a bedroom? Then the ages and blood relationships become more meaningful. If a court is asked to decide a parenting plan or visitation schedule, those factors will be important. But "is it legal"? It's not a crime.