Is there any relation between ewings sarcoma and ovarian cancer?

No: I know no syndrome in which the two run together, but if they did both occur at a young age in the same person, i would suspect one of the cancer family syndromes such as li fraumeni. If there was otherwise a strong family history, or the person wished to make a decision about parenthood, then a talk with a geneticist would be in order.

Yes : Ets fusion genes ( along with braca 2a ) are responsible for 40% to 80 % of ewing sarcoma, ovarian, breast prosttic carcinomas.

Almost never: Ewing's sarcoma is a rare cancer that arises sporadically. There are rare genetic syndromes that predispose patients to a wide variety of cancers. But in the vast majority of cases there is no relation between ewing's sarcoma and ovarian or any other cancer.