The Ragged Princess.

After running away from an orphanage, young Alicia Jones disguises herself as a boy and gets a job on a farm. She falls in love with Harry Deigan, a farmhand who knows her secret, but when the farm's owner finds out, he fires her. Alicia is forced to return to the city, where she meets up with a wealthy man who adopts her. He turns out to be Thomas Deigan, the half-brother of Alice's love Harry Deigan. Harry finds out that Thomas is his half-brother, but also finds out something that could change his, Thomas' and Alicia's lives forever.