In Estates

Are the inheritance rights of an x wife above sibling?

Generally, an ex-spouse is not an heir at law. Therefore, they would inherit nothing unless the decedent left a will that specifically left property to the spouse even if ther (MORE)
In Probate

Is one sibling predeceases a parent do their children get half or does the surviving sibling get all the inheritance?

That would depend on either (a) a will, or (b) state laws of intestacy, or (c) both of the above. Generally: A properly drafted will gives instructions in that situation (MORE)
In Estates

Do the children of a deceased sibling inherit when the sibling dies without a will?

Generally, yes. The property passes according to the state laws of intestacy. You can check the laws in your state at the related question link. Generally, yes. The property (MORE)