I work at the historical society in Vandergrift, Pennsylvania, and we recently received the attached photo as a donation. Written on the back in ink is "Lookabaugh Hawk Reunion Aug. 7-1888, taken at old farm house" the photo is also stamped on the back 1007-B Riffle Photography 559 Bonnie Brae Ave, NE, Phone 5870-3 Warren OH.
I looked briefly on ancestry.com and found an Aaron Hawk who was married to a Harriet Lookabaugh and one of their sons lived/died in Warren, OH. Hope some one can connect--its a great pic!