The Mom needs some counseling about enablement. Seems she taught the boy he can rat out his Dad the next time he doesn't want to do his homework or disobey the rules....putting the authority in the hands of the child.... The article also states that the boy's grades improved when he went to live with his Dad.....who obviously disciplines him properly. Maybe Mom is jealous that she didn't do as well?
My mom lost custody about that age, and yes, she delivered two disciplary nightmares, and yes, she would have had the CPS on him if she thought she could cause him some problems.
This was over thirty years ago. Hell hath no fury...