Tyger Tyger is aimed at younger readers, and brings with it a storehouse of Irish lore. The author uses imagination and creativity to bring these aspects together to create a modern tale. The language is mostly clean, and the violence minimized so it works for that target group.
The story does need more development, in that some scenes are not fleshed out enough to provide a true sense of place, time, and especially feel. Skipping over the mother's death was the biggest hurdle I had with the story, because she was an important part in the character's lives. However they did not act like she was that important. More like an afterthought.
Sometimes the plot seemed lost since so many little adventures took place, when time was, supposedly, of the essence (the father is going to die soon). I thought the main rival character was little more than a lying pushover, and would have wanted there to be more challenge to it.
However, with that said, I think the blossoming romance between the two characters was handled well. There was a good heart in the little brother Aiden, and by the end a lot of good things happened to close out this story, obviously part one of a series.