Penengro

From the preface:

This is an exciting story set in Ireland in which an orphan, Rory, is adopted by a couple because he resembles their dead son. He runs away to escape from this uncomfortable situation, and meets and then lives with a group of gypsies. This book was close to the heart of the author, Hilda van Stockum, as she always sympathized with the outsiders in life. She was also close to nature and had a distrust of machinery, traits shared by the Romanies she wrote about.