Revisit Probate?

What is the name of your state? Washington.

I am 1 of 4 children that inherited a share in a very small piece of
property from my parents estate that 3 of the 4 original children use
for a shared right of way to our homes. My sister, (Who never used the
right of way) died a few years after we inherited this small piece of property. During probate the executor was unaware that she owned a share in this small piece of land and her ownership was never dealt with.

Is there anyway economically to revist the probate or possibly
reinstate her will's executor so it can be dealt with?

You need to be talking to a probate attorney to find out whether sister's estate now has any interest in this property.

The only way that you would need to consider doing anything is if you all decided to sell this property for some reason at a later date, and only a probate attorney or real estate attorney can tell you whether the legal owners names on this right of way need to be corrected NOW or not, whether it is necessary to show the names of all official, legal heirs.