Michigan father charged in mother’s killing after deadly home argument

Ernesto Cuascut-Santini was arraigned Tuesday on open murder and weapons charges after deputies say he shot Marissa Mion more than eight times inside their Oshtemo Township home while their children were in the house. He is being held without bail as the Kalamazoo County case moves forward.

Police say the shooting happened July 5, 2026, at Colonial Manor Manufactured Home Park in Kalamazoo County, shortly after 3:30 p.m., when deputies were sent to the home on a shooting report. Investigators said Cuascut-Santini had threatened Mion in the days before the killing, including an ultimatum that she would either be with him or he would kill her. A later autopsy reportedly removed eight bullets from Mion’s body, confirming she had been shot at least that many times.

When deputies arrived, WWMT reported that they found Cuascut-Santini outside with blood spatter on his face and Mion on the bedroom floor with multiple gunshot wounds. Local reporting also says Cuascut-Santini admitted he fired until the gun was empty and later told others, “I shot my girl.” Investigators say his sister then alerted authorities after he called her and a friend about what had happened.

Mion’s obituary, published by Adams Funeral Home and Cremation Services in Paw Paw, identified her as Marissa Shay Nancy Mion, born Sept. 19, 2000, and said she was survived by her children, Eliana and Jovani, her parents, Lori and Joseph Mion, and her brothers Brandon and Michael. FOX 17 reported that her family wants her remembered as a loving mother and fighter, not defined by the violence that took her life.

The children were in the home during the shooting, a detail that deepens the criminal case prosecutors now face as they build around the alleged threat, the shooting, and Cuascut-Santini’s own remarks afterward. With open murder charges filed and bail denied, the case now centers on what investigators say was warned in advance and carried out inside a family home.