Gwen Stefani has filed for divorce from her husband of 13 years, former Bush frontman Gavin Rossdale, citing irreconcilable differences. As TMZ reports, both musicians are seeking joint custody of their three sons — 9 year-old Kingston, 6-year old Zuma, and 1-year-old Apollo. In a joint statement, Stefani and Rossdale said, “While the two of us have come to the mutual decision that we will no longer be partners in marriage, we remain partners in parenthood and are committed to jointly raising our three sons in a happy and healthy environment.”