Nanette Ubetcha was a TV reporter in Dimmsdale during the 1970's. She has an extreme resemblance to Chet Ubetcha. It could be considered that she is the mother of Chet.
Nanette only appeared briefly to interview a child-aged Denzel Crocker after he had saved young Mr. Turner's life. She told him that the next day, March 15, was declared "Denzel Crocker Day".
Her exact relationship to Chet is unknown, but because she is the around the same age generation as Dolores-Day Crocker, she is likely Chet's mother.
She looks and dresses almost exactly like Chet, although she is much taller than how Chet is usually depicted (likely since she wasn't shrunken by 1980's cell phone radiation), and has longer hair.