Opposite-sex siblings cannot share a bedroom

[snopes]

Comment: I have heard a rumor that it is illegal for siblings of the
opposite sex to share a bedroom when they are over 5 years old. the rumor
continues that child protective services can take your childrena way for
this. The state referenced is Virginia, but in trying to find the truth
of this on the internet, I have seen the question come up a couple of
times more generically. There is never an answer that provides a legal
source.

[wanderwoman]

I don't think this is specified in legislation in most states, but is rather a judgment call. My understanding is that CPS is going to expect to see a reasonable number of bedrooms for a family if they have to do an investigation, and in general if the children are older they are going to expect them to have separate bedrooms for opposite sex children.

This is particularly true if their reason for getting involved with a family is for sexual abuse, for obvious reasons.

[Jay Temple]

This is also very similar to a rule in Missouri for foster homes. Perhaps someone heard correctly but forgot that detail.

[Eve MG]

Originally Posted by Christie

Mike's point wasn't that This Is The Law No Matter What. He is talking about what is generally expected in terms of accomodations, in the case of foster families, and what family court judges may look at when they make child custody decisions.

Not arguing with you, Christie, just this idea in general...

I remember advertisements a few years ago encouraging people to become foster parents, and they specifically mentioned that you didn't need to have a separate bedroom for the foster child. I've searched the NYS Requirements and can't find any reference to how many bedrooms you need.

Looking around some more, it seems some (private?) centers require foster parents have separate rooms for each child, others don't. This one spells it out clearly:

Adequate space – only children under 12 months of age can share a bedroom with an adult. Each infant must have its own crib; each child must have his or her own bed; no child over three years of age can share a bedroom with a child of the opposite sex.

[Judecat]

State of Maryland adoption guidlines. No more than 2 children in a 12x12 rowhouse bedroom, and each room must have a window. (which basically means that you cannot house adopted children in the middle room in a Baltimore row home. over 10 no mixed genders. And if it's not a subsidized adoption, once the papers are signed social services is no longer involved. Once the papers were signed, and I was too big for the crib, I shared a room with my 16 year old brother. My adult brother got the middle room. Just after the older brother moved out, I had my own room for 6 weeks, til mom adopted another little girl.
However if you are not involved with social services, there really is not law about who sleeps where. My brothers two son and daughter slept in bunk beds until Middle school, when they converted the large bedroom into two small ones. And those rooms were so darn small, my walk in closet is bigger.