Do I have to be present at the probate hearing for my father's estate if I live in another state?

I am so sorry for your loss. It is always best to be present at any proceeding that may effect your rights under the law, what ever your rights owuld be.  Here they are to inherit.  That being said it may be less expensive to hire an attorney to be present for a flat fee and to report on the matter.  If you think that nothing funny is going on and everyone is on the up and up and you have received a copy of the Will and proper notice then the final decision is up to you.  Good luck.