Custody Thing . . .Again

Okay - the short version: my ex and I just started a 50/50 custody split this past Saturday. He will have the kids, who are 7, 14, and 17 the first through the 15th of every month. They will be with me from the 16th until the end of the month.

The questions is really I am looking for advice - since Saturday the 14 year old has been home alone Saturday night, and home watching his 7 year old sister - all day Sunday (ex working), all day (from 8 a.m. until 10 p.m.) Monday - ex working again, all day Tuesday 8-4, and then last night their Dad left them again to go bowling on his bowling league, this time taking the 7 year old with him. He got back home with her, on a school night, at 10:15.

The 17 year old has a job and his own car, so he is pretty much free to come and go as he pleases, so he is not stuck there.

The boys are not happy but are still willing to "work it out." They asked me to talk to their dad. I know his response with me will be hateful and to be honest, I don't want him trying to tell me how to raise the kids when it is my time. I am really concerned about the 14 year old taking responsibility for his sister so much and the 7 year old not being on any type of schedule and the ex thinking it is okay to have her out so late.

Any thoughts????