You might perhaps be very skilled, and able to institute legal proceedings and write legal briefs as well as some attorneys. But if you're a layperson, one of the things that you often cannot do either competently or legally is to represent an estate in civil proceedings outside the probate court.
First, as the Court of Appeal holds, you're not allowed to. Second, even if you were allowed to, it's generally not a good idea. If only because, among other things, you generally don't know what you don't know, which in turn can be fatal to your petition.
Get a lawyer.
