Mrs. Kataoka

Mrs. Kataoka, more commonly referred to as Grandma Kataoka, is the mother of Tamako Kataoka as well as Nobita's maternal grandmother. She rarely makes an appearance with most of it in the past that has Nobita and Doraemon travels to the past but also appears in Gourmet Table Episode and We're Gonna Steal Mom's Diamond. Most importantly, she was also the mother-in-law of Nobisuke Nobi.
She looks similar to Tamako, Nobita's mom and has brown hair in the old 1979 version and black hair in the manga and 2005 anime. She looks more similar to Tamako in the 1979 appearance rather than the 2005 one. She wears different glasses which her glasses are rounded circle in 1979 and rectangular in 2005 anime.
She, along with her husband, are the only living grandparents of Nobita.

(Source: Doraemon)