I am my mothers executor and want to sell her home to my sister.

You will need to have the will probated in order to transfer title to your sister for the sale of the home. Otherwise, the house will remain in your deceased mother's name. Because your mother left a valid will, you need to have that will probated; however, if your mother did NOT have a will and had owned less than $50,000 in assets (excluding her homestead, which I'm assuming is this house), you may have been able to do a small estate administration, which is like an abbreviated form of probate. This would allow you to sell your mother's property to your sister and collect on any money she may be entitled to (pensions, 401k accounts, etc.) Because your mother left behind a will, however, this is not an option for you.