SOLVED. Book about a boy and a girl who live in different worlds/universes; they are essentially the same person apart from their gender, and their worlds are pretty identical bar one difference - The boys mother is dead, the girls is not [s]

[Dara]

The book is about a boy and a girl who live in different worlds/universes; they are essentially the same person apart from their gender, and their worlds are pretty identical bar one difference - The boys mother is dead, the girls is not (and their mothers are the same people too).
The boy accidentally manages to travel to his female self's world, using a wooden model of their house that his mother made years earlier.
The cover was largely blue (on my copy anyway), it IS part of a serious, and it didn't seem like a very old book (90's or 2000's perhaps).

And that is basically it. REALLY want to find this book, hopefully the plot details are enough. Any help would be much appreciated. Thanks =)

[Alycia]

Would you say that this was YA fiction? Or a younger reading level? Or an adult book that just featured kids?

[Sue]

Is this The Aldous Lexicon trilogy by Michael Lawrence? "Naia Underwood has a double in another version of her reality: a male double called Alaric. For almost seventeen years their lives have been identical but for one thing. Alaric's mother died following a train derailment two years ago - the same derailment that Naia’s mother survived. Now, Naia and Alaric are about to meet for the first time, with disastrous consequences for one of them...

A CRACK IN THE LINE is the first of a much-praised three novel sequence called The Aldous Lexicon. Volume two is SMALL ETERNITIES, volume three THE UNDERWOOD SEE. All three are also available as a single ebook, titled simply THE ALDOUS LEXICON.

Set in England - primarily in 2005 but ranging back and forth over many years - the trilogy was originally published in the US by Greenwillow and HarperTeen as The Withern Rise Trilogy. The ebook editions are revised versions of the print volumes, with some additional material and considerable re-editing."

[Lou]

Sounds like the Aldous Lexicon to me too.

For the clicky (both british and american covers):

[Lobstergirl, au gratin]

Dara, as you read in the pop-up box when making your comment, please add genre and plot details to your header to make it easier for people trying to solve threads.

[Dara]

A Crack in the Line, that's it =) Thanks a million guys, all three of you were spot on, so glad because I never would have remembered that name... Thanks again guys!

Will take that into account Lobstergirl, will move this to solved folder now too :)