4yr. old making herself vomit

I am looking for suggestions on how to talk with the parent of a child i watch.  The child is 4, recently went through a nasty divorce, dad is not involved and when he is its always a negative turn out.  She started coming here last year and would make herself puke when her mom dropped her off.  She did go through some really bad seperation anxiety during that time and I found that if I calmly talked her down, she wouldnt get sick.  This behavior did not continue on a regular basis but from time to time, especially if there was a break in coming to my house, she would still make herself sick here and there but then for the last 6months it hasn't happened again at all.  Untill recently, after a break at christmas and a let down from her non involved father, and a change in her living situation with mom and going to moms boyfriends, She is now doing it AGAIN.  At first we thought she was really sick because the flu has been going around.  But there were never any other symptoms, and she played like normal right after everytime.  This has been going on for about a couple weeks now and Today I walked in the bathroom and caught her with her head in the tolit trying to make herself puke, i talked her down calmly and she never got sick, but how can i keep this up when the children are supposed to be napping, BTW it only happens when she's in the middle of nap now which im sure all kids arent totally excited about nap but they really need it.  It has also happened with her mother when they were visiting the new boyfriend and all in the same bed.  I know NIGHTMARE right?? but seriously she is a great kid and im just trying to find a way to help her out.  She has been checked medically and nothing came back. She has not seen a child psychologist however and Im really starting to think this may all be in her mind.  Any suggestions on how to handle this, talk to the parent about it, and how to help the child calm herself down enough to not try and make herself sick... Also, FYI i have suggested in the nicest way possible tothe mother that she may be doing this for attention or just that she may be making herself nervous enough to get sick.  I have asked the child if she felt bad, NO, if her tummy hurt NO, did u just wanna get up from nap, YES!. And ive communicated all this to the mother but she doesnt seem to buy it.  Guess im just looking for the best way to help her when she's here because i know thats about all i can control.. Thanks! in Advance for any insight that might help

[AnnieBrooke]

Do you suppose her mother also makes herself vomit, and that is where the child learned that this will work for her to get out of whatever (i.e., taking a nap or other things)?  

The whole thing sounds awful.  In bed with the mom and some boyfriend?????  The poor kid, it sounds like you are the only stability in her life.  Her father, a loser, her mom with no sense of how to be a mother.  (The mom has no business even having a boyfriend stay over.)

Sorry, I don't know what your duty and responsibility is here, the poor kid is just at the end of the dog's tail and the adults (except you) are NOT acting with her best interests at heart.

[Sandman2]

   Probably not a factor, but do the kids eat anything before they nap?
  And frankly, if this only happens during the nap, I would find something else for her to do to help you instead of napping.  Maybe even sweeping outside (perhaps she might decide the nap isn't such a bad idea).  And I really don't mean the job as any kind of a punishment - but heck give her something to do where the other kids maybe can't see her - and see what happens.

[gitsum]

there could be sexual abuse involved, or she learned this behavior somewhere. irregardless, you need to teach her about having a healthy body image and about how being healthy is important and what she is doing will only make her unhealthy to the point where she could become sick and suffer permanent damage.