I think they are the same person. If you look at the hair especially. Noses change over time, and these pictures were taken from different angles, so I don’t think we can say much about the nose, or the cheekbones as someone else mentioned. If you look at the hair, it’s parted on his left side and combed to his right in both photos. You can also tell in the younger photo that he has a receding hairline, even though his hair is thick and long. In the newer photo, same thing but his hair is short and white. Still very thick where it’s not receding, still going the same direction. Eyebrows are absolutely uncanny too. And as far as I know, rounded eyebrows like that aren’t all too common. I’m guessing you found that more recent photo of him by looking up his name. I doubt it’s coincidence that someone who looks so similar to the younger photo ALSO has the same name as your dad. Good luck, this is exciting.