Proctor, Maggie's older sister, is the first family member to testify at Alex Murdaugh's double murder trial.
Murdaugh, 54, is accused of fatally shooting his 52-year-old wife and his son, Paul Murdaugh, 22, in June 2021 near the dog kennels of the family's sprawling hunting estate known as Moselle in Islandton, South Carolina.
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Alex Murdaugh, left, bows his head as his sister-in-law, Marian Proctor, testifies Feb. 14 on behalf of the state at his double murder trial in Walterboro, South Carolina. (Fox News )
Maggie didn't want to go home that evening. She often stayed at the family's beach house in Edisto, but Murdaugh's father had just been admitted to the hospital.
"I said, 'Maggie, Alex and his dad are super close, so that’s probably what you should do, go be with him if he needs you," Proctor testified of her last conversation with her sister.
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Lead prosecutor Creighton Waters asked Proctor if she had pressured Maggie to go to Moselle June 7.
"I did," she said, dissolving into tears.
The next day, she learned of the shocking tragedy. "I just couldn't believe it," recalled Proctor, who had to deliver the news to their parents. "It was just the worse."
A photo of the Murdaugh family taken days before Paul and Maggie Murdaugh were shot to death. From left, Buster, Paul, Maggie and Alex Murdaugh. (Defense exhibit)
After the murders, Murdaugh allegedly told her whoever committed the heinous crime had "thought about it for a really long time," she said.
He also spoke a lot about the 2019 boat wreck that killed 19-year-old Mallory Beach.
Paul, who had a blood alcohol level three times the legal limit, was driving his father's boat when he crashed into a bridge, killing Beach and injuring four other friends.
The accident led to a wrongful death lawsuit against the Murdaughs that set off an unthinkable spiral of destruction.
Alex Murdaugh (left) and his attorney Dick Harpootlian listen to Chris Wilson’s testimony in Alex Murdaugh’s trial for murder at the Colleton County Courthouse on Thursday, February 9, 2023. (Andrew J. Whitaker/The Post and Courier/Pool)
Proctor said after the killings, Murdaugh was very intent on clearing Paul's name.
"He said that was his No. 1 goal," she testified. "I thought that was so strange because my No.1 goal was to find out who killed my sister and Paul."
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Proctor described her sister as a "really good person" and a "free spirit" who was devoted to her family.
"Buster and Paul were her world," she told the jury. "She didn't care what they were doing, she wanted to spend time with them."
Paul, Alex, Maggie and Buster Murdaugh at a sporting event. Alex is accused of fatally shooting his wife and son. (Facebook)
Although Maggie was a girl's girl, she would accompany her son's fishing and hunting to be near them.
"She would get in the hunting stand with her sons, and the boys would tell her she was making too much noise turning magazine pages," recalled Proctor, eliciting laughter from the courtroom.
She described Paul as a "sweet, sweet boy" who was "always wanting to help."
On cross-examination, Proctor said that Murdaugh was destroyed by the slayings.
Although Maggie and Paul's marriage wasn't perfect, she said they were happy.
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She added that Murdaugh and his son had a very good relationship. "They loved all the same things. They loved to hunt, they loved to fish, they loved to work the land," she testified. "I think the plan was for Paul to take over Moselle one day."
Maggie had confided in her sister that Murdaugh struggled with an opioid addiction.
Maggie called her son the "little detective" because if there were pills in the house that his dad shouldn't be taking, he was determined to find them.
Proctor said her whole perception of Murdaugh changed after the Sept. 4, 2021, roadside shooting.
She soon learned that the shooting was staged, and Murdaugh had been fired from his law firm for allegedly stealing millions of dollars.
Murdaugh allegedly hired Curtis "Cousin Eddie" Smith to kill him so his son, Buster Murdaugh, could inherit a $10 million insurance policy.