Infinity's Edge (Lost in Space, Bk. 2)

The Robinsons--Will, his two teenage sisters, and their parents--are members of a colonist group who had been traveling across the galaxy to establish a new home, only to have had their ship attached and stranded on an alien planet. Just when they had finally managed to get off-world, the Robinsons were thrown off course yet again and were sent drifting toward an unknown location.

Now, six months later, the Robinsons are stuck on an inhospitable water planet with no contact from their fellow colonists or from Will's beloved Robot. The twelve-year-old doesn't have any friends in his new home, until he discovers a mysterious girl...from the future. Her name is Clare, and she desperately needs Will's help to save her family. Will is eager to bond with his new friend, but--little does he know--something sinister lurks just beneath her surface. Can Will find a way to help Clare while keeping his own family safe?