A wedding photograph.
The groom resembles the man in the back on the left in the wake photo. The man standing on the right also resembles someone in that photo. Complete conjecture leads me to wonder if this could be a wedding of John Whalen & Margaret Flannery, 1/18/1910 St. Clair, PA. The man on the right might then be his brother Charles Whalen (age 21 at that time).
This is all wild speculation!
[Studio: UNKNOWN]