Kinkade's widow is struggling to retain control of the estate against his live-in girlfriend.
Amy Pinto-Walsh claims two hand-written wills leave her Kincade's Monte Sereno mansion, plus $10 million to establish a museum of his artwork.
Lawyers for Nanette Kinkade,his wife of 30 years, filed papers on Friday contesting those wills.
Kinkade died in April from a fatal combination of alcohol and valium.