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...
I don't understand some wimmen.....and yes I know their are different circumstances... but I'd have given anything if my ex would have participated in adequately disciplining the kids. The job is to get the kids raised as best you can. If you focus on that....you'll find you have no time or energy to waste on vindictiveness.