What's Your Name?

What I know: This photo was in my grandfather, George "Buddy" Mariencheck's, picture box. At left is Gertrude McKee Grace. Agnes Grace Ferrer is in the center. The  man is a mystery.  I assume by the casual, familiar way they're standing that this is one of her brothers. But I'm not sure which. Based on age, it could be Raymond or Booth. The picture isn't fully focused, so it's difficult to tell.  Or is this someone else entirely? Do you know who this is?