She needs to get him out of her bed! There are two issues: first, hers with co sleeping with a near to start pubertal male child and infantilizing him by doing so.  Second, his perhaps confusion over your status as a six year boy friend if you too share the bed (not recommended).  I suggest you start by explaining to this fourth grader that he is to stay in his room and bed at night. Read Ferber's book on sleep disorders in children or get help from your local mental health group to make a behavioral change. You both need to be in agreement with the change and stand firm.  Sleep issues for older children are difficult to attend; however, with rewards and praise and a firm plan, you can succeed.  It is HER child, not yours, so she needs to be in charge.

Wayne Yankus, MD, FAAP
expert panelist: pediatrics