Thanks to Chris at ASD Blog for turning me on to Elsewhere by Gabrielle Zevin, a wonderful book that I would recommend to anyone mourning the loss of a loved one, especially a young person.
Our protagonist, Liz, is just fifteen when she's killed in a traffic accident. She awakes on a cruise ship bound for the island of Elsewhere, where her grandmother (who passed on before Liz's birth), meets her at the dock. Liz has some trouble adjusting to her new afterlife, finding a vocation, falling in love, driving a car without a license. Folks on Elsewhere age backwards until it's their time to be born again on Earth, and Liz is frustrated (as many adolescents are) about being on the edge of adulthood. Ever as she grows younger, her outlook on life matures as time passes.
I like to imagine my cousin Tatiana, who passed away on May 26, 2005 at the age of 18, having an afterlife like Liz. She'd have two grandfathers and a grandmother to look after her, three aunts on her father's side to hang out with,