Ionia County Sheriff's Department released new details regarding the murder-suicide that occurred on Jan. 6, 2018.

The incident led to the death of a husband and wife, Lisa and David Somers, and new details reveal the couple were arguing prior to the shooting.

Amedy Dewey, 18-year-old daughter of Lisa Somers, sustained a bullet wound and is currently recovering in the hospital, but has since provided police with additional information.

Lisa Somers and her daughter, Amedy returned to Michigan from a Florida cruise vacation on Jan. 6. David Somers was meant to join them on vacation, but he opted out the day before they left.

David picked them up from the Gerald R. Ford Airport in Grand Rapids upon their return and started driving toward Midland, Mich. via I-96, where Dewey was going to be staying with a friend.

David and Lisa were continuing an argument that started earlier in the day by phone. Lisa made accusations of David's infidelity. The argument escalated and David Somers started driving erratically before he pulled their 2011 Chevrolet Equinox off the expressway.

David got out of the car and walked to the back of the vehicle, where a shotgun was stored.

Amedy reported that her mother then shouted "he's got a gun!"

Amedy told detectives she immediately got back into the car in the back seat, and tried her best to lay across the seat and hide from David.

Amedy said she tried to call 911 right before David shot her in the head with a 12 gauge slug, which caused severe injury. David shot her from the opened lift gate. Amedy said she did not see what happened to her mother.

According to the release, Amedy told Ionia Sheriff’s Detectives that her immediate instinct was, “I’m not going to die. This is not how I’m going to die!”

Amedy then took steps to save her own life by climbing over the front seat to use the horn and lights on the car and eventually got out of the car to flag down passing motorists.

Witnesses called 911 but at that point the extent of the situation was not clear to anyone passing by. Investigators were able to determine at the scene that David then shot Lisa once with the same shot gun before turning it on himself. The gun was found under his body at the scene.

It is still unknown if David Somers was under any type of influence at the time, toxicology reports are still out.

Ionia County Sheriff’s Detectives are still working to gather further information about the crime and anyone with details is urged to call their office.

In the release, the sheriff's department also noted their respect for Amedy's efforts that night.

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