Stacy Chapin is reflecting on her son Ethan Chapin's life.

Seven months after the 20-year-old was murdered along with fellow University of Idaho students, Maddie Mogen, 21, Kaylee Goncalves, 21 and Xana Kernodle, 20, Stacy opened up about how her family—including husband Jim, and surviving triplets Maizie and Hunter—is doing in the wake of tragedy.

"It's a different dynamic in our home without Ethan," Stacy said on Today June 5, "but we work every day on it."

She went on to recall how Ethan was a natural born leader—quite literally, as he was the oldest of her triplets. 

"He was definitely the glue that kept all of us together," she continued. "He was funny and inclusive, and he always made sure that Maizie and Hunter were included and loved. He was born with the kindest soul."

And Stacy wanted that to be known. So, the mother of three wrote a children's book, The Boy Who Wore Blue, inspired by her late son, with the title reflecting on the color he wore most often as a child. 

She explained that she took it upon herself to write Ethan's story after learning a book about the murders was being written.

"I'm the one who raised him and it just sparked something in me," she told host Jenna Bush Hager. "It just came to me in the middle of the night. It's the best I can do for him."

As for how his siblings, who also attend the University of Idaho, are coping with the loss?

"Jim and I couldn't be more proud of them," Stacy revealed. "They went back to school, they finished the semester successfully and now they are back at work at a place they love that we've called summer home for a long time."

She added, "They are doing amazing. I am so proud of them, it's amazing."

Stacy and Jim are also honoring their late son through a foundation called Ethan's Smile, which gives scholarships to local students to attend the University of Idaho.

"What we find more interesting is how many lives he touched that we didn't even know existed," Stacy continued. "It's incredible. I tell people if I touch as many lives in my lifetime as he did in twenty years. He just swarmed every room. He had a wonderful smile."

And as Stacy and the Chapin family continue to honor Ethan and keep his memory alive, they do not intend appearing at the upcoming trial for his accused killer.

"We chose not to," Stacy explained. "It does not change the outcome of our family and it's energy we need to put into healing our kids and getting back to a new family dynamic and working on that."

She noted, "We let the prosecutors do their job and we do our job."

Bryan Kohberger was indicted May 17 on four counts of first-degree murder and one count of burglary in the November murders of Ethan, Xana, Maddie and Kaylee.

According to court documents obtained by E! News, an Idaho grand jury concluded that the 28-year-old "did unlawfully enter a residence" in the town of Moscow last November and "wilfully, unlawfully, deliberately, with premeditation and with malice aforethought, kill and murder."

However, he has denied any wrongdoing in the case.

"It is a little out of character, he said. This is not him," his public defender, Jason LaBar, told Today in January. "He believes he's going to be exonerated. That's what he believes, those were his words."

His murder trial is set to begin in October 2023.

For the latest breaking news updates, click here to download the E! News App