Is Luke from Professor Layton some kind of orphan or something?

My little brother started playing Professor Layton games and this has really been bothering me. Where are this kid's parents and why are they letting him run all around the country with some random dude? Are Luke and the professor related? Did professor Layton adopt Luke or something? Does Luke ever write home???|||It's never explained in the English language releases so far, but it will be explained in the fourth game in the series, Professor Layton and the Specter's Flute (as far as I know). That game is a prequel to the first 3 games, when Prof. Layton first meets Luke. So far we only know that Luke is a self-proclaimed apprentice of Layton.|||He has a father who is a friend of Professor Layton.|||lukes dad knows prof.layton. how layton came to meet luke and why luke is running around with him will be completly told in the fourth game.