Grandma Gertrude "Gertie/Pookie" Shortman (born c. 1917) is a fictional character from the animated series Hey Arnold! She is Arnold's wacky, but wise paternal grandmother, Phil's wife, Miles's mother, Stella's mother-in-law, and Mitzi's sister-in-law who is the co-owner of the Sunset Arms boarding house with her husband and is often seen doing outlandish things, including dressing up and acting like fictional characters and/or historic figures, mostly when serving meals to the boarders. Gertie has known her husband since they were in grade school and has had a relationship with him that was similar to Arnold and Helga's own when they were their grandson's age, except her pranks were more vicious and extreme. During her early adulthood, she once worked as a police officer and earned a black belt before she married Phil.