According to unconfirmed sources, A cousin or uncle lived with the family for part of 2011. 2011 ended (obviously) in December. CPS was in contact with the family in December.
If the family had decided to allow the cousin or uncle, who may or may not be JM, to use Isabel's room while getting settled in the area, this would explain the (similarly unconfirmed) assertion that Isabel slept in the boys' room. Perhaps in a sleeping bag or bedroll, on a cot, or in a pup tent. We do not know for sure that she shared a BED with either boy. It is possible that the oldest of the sons was venting to his friends about having to share his room with the "babies" including his sister, and how he had no privacy. CPS would NOT approve of this sleeping arrangement, and this COULD POSSIBLY have been the end of the line for the houseguest, as Isabel had to return to her own room. It would not necessarily mean anything inappropriate happened to Isabel or the boys, but that CPS has certain guidelines about opposite gendered children sharing sleeping space.