Son of Summer Stars — Meredith Ann Pierce

The Final Volume of the Firebringer Trilogy

A secret haunts Jan's dying father, Korr -- a secret so dark that, if exposed, could bring the downfall of the Firebringer. Jan is left with its terrible burden, and an impossible choice -- renounce Tek, his beloved mate, and lose forever the kingship of the unicorns, or return and face the consequences of his father's acts, and of his own.

"A first-rate ending for a fine fantasy series." -- Booklist