It does look like Eko, but as someone else pointed out already the hairline is off, Eko had a lower one, and the boy's eyebrows in the picture are much thinner than Eko's were. It is possible that the prop department wanted to have young Eko in the house and asked the actor to send in a photo and that photo could have been more recent or more earlier (?) from the time we saw this kid in the episode. Eh. Couple of interesting things here though:
1. Both Eko and grandson made criminal choices at a young age. Both ended up dealing drugs and making a lot of money for it. And both ended in someone's death- grandson died himself, and indirectly Eko killed Yemi. But both cared very much for their relatives at the same time. Very similar stories hm?
2. Frames changing. And the fact that this woman has 2-3 copies of the same photo in her house. I agree, it does seem like we were really MEANT to see this kid's picture. Was it because it was Eko? Maybe, but that doesn't really make sense. I feel that it was just for the human emotion part...this guy Miles doesn't really seem to enjoy his gift that much, but he uses it anyways to stay alive. I think having him look so intently at the pictures showed that he does have a human side, even after he just stole a bunch of money from upstairs.