Joseph Germanotta, to whom the singer dedicated a song at a concert earlier this year, passed away on Friday.By James Dinh Lady Gaga Photo: Kevin Mazur/ WireImage Lady Gaga's grandfather, Joseph Germanotta, died on Friday at the age of 88. Germanotta reportedly suffered a long battle with Parkinson's disease. On Sunday, Gaga remembered her late grandfather via Twitter, writing, "Having a Perfect Manhattan, for my perfect guy.