Kouri Richins, 35, faces charges of aggravated murder, attempted aggravated murder, insurance fraud, and forgery in connection with her husband's death.

A key witness in Kouri Richins' murder trial testified Thursday that she obtained the fentanyl that prosecutors allege Richins used to kill her husband of nine years.

Add Yahoo as a preferred source to see more of our stories on Google. The murder trial of Kouri Richins, a Utah mom accused of fatally poisoning her husband with fentanyl who self-published a children's book on grieving following his death, is set to get underway with opening statements on Monday.