Oona Sperr, 64, has filed a lawsuit against billionaire oil heir Sid Bass, 84, claiming he abruptly ended their ten-year relationship in September 2024 before marrying socialite Althea Irene Viafora Kress, 68, whom she accuses of manipulating Bass to force her out. The suit, filed in federal court and worth $400 million, alleges Bass was in declining health, having suffered mini-strokes and a Parkinson's diagnosis, and claims Kress took advantage of his condition to insert herself into his life over roughly two years before the split.

According to the lawsuit, Bass ended things at their Pagosa Springs, Colorado ranch during breakfast, telling Sperr "I want a separation. You are to pack and leave," and later allegedly offered her $50 million and two homes to leave quietly. Sperr claims Kress ordered Bass to cut all contact with her, remove her belongings from their shared homes and avoid taking her to the airport, and that she learned of the couple's August 2025 wedding on Bass's private Texas island only via a brief email she suspects Kress actually wrote.