What is a Child Family Support Meeting with the Social Services?

My ex-wife was reported to SS for not making sure that our two girls (Ages 11 &6) went to school like they should, posting a pic of her boobs on her myspace page where our daughters can see them getting a citation last year for having an ounce of weed on her and having our girls sleep in the same room as her and her boyfriend, among other things probably. These are just the few that she has admitted to me about. SS will not tell me anything at all. I'm so worried. She has also lied to them about her boyfriend living with her and that the girls sleep in the same room as her and her boyfriend. Anyways, the Child Support services case worker has scheduled a Child and Family Support Meeting for Monday and I was asked to come. The case worker also says that my two daughters have to be there. Why does SS usually schedule one of these Child and Family Meetings?

P.S. (yes, I tried to make her take them to school but in doing so I was falsly arrested by my exwife when I showed up at the house two mornings to take them to school myself (charges were dropped since they were false).So please dont think that I didnt try to get them to school.