Sculptor. He attended the School of Applied Arts, was a pupil of Alajos Stróbl, then learnt in Vienna and Munich. He went to Rome on a scholarship of the Society of Patrons. On his return to Budapest, he settled down in Gödöllő where he was in touch with Aladár Körösfői Kriesch: Sidló and Körösfői Kriesch produced the coronation relief for the Hall of Culture in Marosvásárhely.

He was a teacher of the Art School from 1926 onwards. He received a lot of commissions to create memorials and portrait statues between the two world wars. His best-known works are the statue of "King Stephen" (Székesfehérvár) and "The Fountain of the Danaides" (Budapest).