I only have questions from your post. Is grandmother alive? Does the will say what happens to the estate if grandmother is dead. If not, then...

Have non responsive sibling served with court papers. See an attorney. ……………………………………………………………………….

Sell the house and split the money according to state law. Oh yeah, see a lawyer. ……………………………………..

Talk with overseas attorney about whether to begin the probate of fathers estate there or in the us. Not much of a problem if mother is...

Lots of considerations go into the likelihood of success of a will contest. Most information necessary is absent from your post. See an attorney.

You need a death certificate? Order one from vital records. ………………………………………………………………………….zzzzzzzzzz….

Did sister open an estate for father? If not the probate court has no jurisdiction. Perhaps you need probate father’s estate and sue for return of...

Sounds like two estates need to be established. Living in a house that is not yours with permission of the owner establishes no new ownership...

Sounds like a dispute over whether there was a valid gift of property before decedent died. Take her to court. You need a lawyer.

You have no standing to file anything if you are not a beneficiary of the will. If you are a beneficiary, probate the will and once appointed as...