Most time travel stories take a person back, or forward--they are still themselves. More rarely, the central character becomes part of someone else's life, thinking that person's thoughts, seeing what that person saw. At the Firefly Gate (2004) by Linda Newbery, uses that later sort of time travel, and mixes it, very gently, with a bit of ghost story.
Young Henry is cross at the world, but in particular with the parents who moved him from his happy life in London off to a village cottage in Suffolk--the summer ahead seems lonely and pointless. But although Grace, the slightly older girl next door, lives up to his expectations and is hostile, Henry's first weeks in his new home are not at all what he expected. There's Grace's old aunt, Dotty, slowly dying but full of life. There are friendly kids in the village, who take Henry into their world.
And then there is the man who stand by the gate outside Henry's house in the late evening, smoking, and waiting...while all around him flash the lights of fireflies (and the author actually does make clear that these are glow-worms, this being England, just in case you were worried about that point).
Henry feels drawn to this mysterious man, who no one else seems to see. And stranger still is that, from time to time, Henry finds himself briefly living bits that man's memories....of life as a young man in the air force, in World War II.
In the garden next door, Dotty still wonders what happens to the Henry she lost long ago, when his plane never came home. The modern day Henry's memories of the past hold the answer, if he can bring himself to talk to her about what he has seen.
And by the fire fly gate, the other Henry is waiting...
I first read about this one over at The Children's War, where you can find a more detailed synopsis, if you are so inclined. I heartily agree with what Alex says about this one--that the main characters, Henry, Grace, and Dotty, are believable individuals, who, more to the point as far as my reading pleasure is concerned, I found likable and interesting (even prickly Grace!). And it was just simply nice to read about a moving, unforced and unpreachy friendship between a boy and an old woman.
The timeslipiness and ghost-ness added just the right amount of poignant magic, and if I never was that much the wiser for why Henry in the present was able to channel Henry from the past, I didn't care.
So all in all, a very satisfying mix of the mundane life of kids in an English village with memories and mysteries from World War II. Strongly recommended to people who like the same books I like,* who will find it pleasantly diverting.
*which is totally different from recommending a book to all and sundry. This is why I dislike giving stars--this one, for instance, I feel is a solid 4.3381 (I thought about that number for a long time; it is not meant to be funny) on the scale of my personal taste, but yet I hesitate to press it wildly and extravagantly into the hands of all comers, because it is driven by character and emotion, with not much that happens, and it has a dream-like quality that some might find chaffing (and Henry's blossoming social life would be hard for a cynic to swallow). In short, it's all very Difficult, this reviewing thing.
But I'm glad that Alex recommended it strongly enough so that I picked it up.