Both Tom and Leslie were teenagers when Laurel took an interest in them.Polly gets a bit of a crush on him as a teen, but they don't actually start a relationship till she's in college.

They meet when she's a child, and he's old enough to have been married.

They aren't related to the main plot outside of their effect on Polly's state of mind because they care too much about themselves to get involved in it. Polly's father is a feckless, Dirty Coward who tries to coddle his wife by treating her moods as a joke, which only makes them worse, and they both attempt to use Polly against the other, without much thought or care for her at all. Her mother is paranoid, controlling and nagging, but believes that she is a long-suffering martyr who gives up everything for other people, and she sinks into spiky moods when things aren't to her liking. Adults Are Useless: A depressingly realistic version with Polly's parents.But when she realizes so many bits of her life don't make sense, she slowly uncovers her hidden memories and becomes determined to find out what happened to her friend. Now nineteen and preparing to leave for university, Polly has no memories of Tom or anything to do with him.

Together they created stories in which their alter egos were heroes - but soon things from their imaginary world became real (though not always as expected), and Tom's mysterious relatives persistently badgered Polly to stay away from him. While staying at her grandmother's, Polly Whittaker wandered onto the grounds of an old neighbouring mansion, Hunsdon House, and met a man called Thomas Lynn, with whom she struck up a peculiar friendship. A novel by Diana Wynne Jones, based on the stories of Tam Lin and Thomas the Rhymer, with a 1980s setting.

Fire and Hemlock by Diana Wynne Jones