Yes indeed! We are in the same family! John Garis (your grandfather) and my grandfather, Abraham(Abe) were brothers. I don't know if we ever met, although as child we would visit my grandparents in Reading. Your mother's brother, Chet and his wife, Grace, were the main family members I knew as a child, although we visited Betty Mason, as your grandfather lived with the Mason's here in Florida. Bobby Mason was a bit older than my sister (Verlane) and I, so we never knew him very well. I am still in contact with Chet's children, Gerry, Skip and Bonnie and see them when they visit Florida. My Mom just celebrated her 97th Birthday in July, but my Dad died about 26 years ago. My sister also died unexpectedly almost 5 years ago.
As for the "Mahlon's" in the family there were several. My Dad was Mahlon Augustus, but he was named after his Uncle Mahlon Stanley, Abraham and John's brother. I have photos and stories, but have not had time to assemble much to add here since I take care of Mom. Please send a note if you would like to exchange emails and more info.
All my best,