Complex sentence: Elina Taalasmaa is the daughter of Ulla Taalasmaa and Martti Viljanen, but she considers Seppo Taalasmaa her real father.
Split into simpler sentences: Elina Taalasmaa is Ulla Taalasmaa's and Martti Viljanen's daughter. Elina considers however Seppo Taalasmaa her real father.