It is not uncommon for an executor to discover an asset of the deceased, even after a grant of probate has been made. When this happens, there is a procedure to be followed. The executor must determine the value and ownership of the asset. Once ownership is confirmed as being in the deceased, then the executor must draft a supplementary affidavit describing the asset. The executor must file the supplementary affidavit with the court registry, and pay the probate fee owing on the asset. As part of that effort, an amended Statement of Assets and Liabilities should be filed, as this is necessary for disclosure to Canada Revenue Agency for tax purposes.
It is not needed to obtain a “new” grant of probate. It is sufficient to disclose the existence of the newly discovered (or received) asset.