Janel Parrish wed Chris Long after his father was killed as he rode his motorcycle in the morning

Janel Parrish‘s wedding was bittersweet.

The former Pretty Little Liars star, 29, revealed via Instagram on Saturday that her father-in-law, Herbert “Buck” Long, was killed by a drunk driver just two weeks before her wedding to Chris Long.

“A few weeks ago, we got the awful news that my now father in law was tragically killed by a drunk driver on his beloved Sunday motorcycle ride,” she wrote. “Words can’t explain the feeling of losing someone to something so senseless… something that could have been prevented.”

Alongside a picture of Buck toasting the happy couple at their engagement party in February and a photo from a motorcycle ride, Parrish called on her followers to help Mothers Against Drunk Driving.

“Please read about his life, and if you’re moved by his story, help donate to MADD to help make sure this doesn’t happen to anyone else. Link in my bio. Love you Buck,” she wrote.

Buck Long

Parrish and Long got engaged in October after dating for over a year and tied the knot on Sept. 8 in a ceremony in Hawaii attended by PLL costar Brendan Robinson and showrunner I. Marlene King.

The next day, she wrote on Instagram, “loving my husband so much.”

According to the MADD fundraiser set up by his kids, Buck died at age 74 on Aug. 26. “He was driving in traffic, at 6:30 in the morning, when an 18-year-old intoxicated driver ran into him head-on. Buck was killed instantly,” the page explains. “The driver then fled the scene, but was later found by police hiding in a nearby ravine.”

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Buck grew up as the son of a military officer and served in the U.S. Navy. He married wife Victoria in 1972 and the couple went on to have three sons — Travis, Colby and Chris, all of whom worked for him at Harpure Enterprises — and three grandchildren.

The fundraiser noted, “Buck’s passions in life were his family, his friends, his company, his motorcycles & cars, working with his hands, cycling & running, snowboarding & surfing, the Rotary Club, and the Oakland Raiders. Those that knew him will tell you he was the youngest and healthiest 74-year-old anyone has ever met. He will be sorely missed by all those whose life he touched.”

At the February engagement party, held at Beauty & Essex in Los Angeles, Buck had spoken lovingly about Parrish and his son. “Their fathers gave speeches saying how blessed they were to see their children so happy and how excited they were to see them both start a beautiful new chapter together,” a guest exclusively told PEOPLE at the time.

Janel Parrish’s engagement party
| Credit: Orsoya Sierra Orsoya Photography
Janel Parrish and Chris Long
| Credit: Orsoya Sierra Orsoya Photography

“Janel and Chris were both glowing all night and looked happier than ever,” the guest continued. “They left hand-in-hand talking about their wedding and how thrilled they were to continue the planning process.”

In May, Parrish told PEOPLE that she was most looking forward to writing her own vows.

“We are probably both just going to cry like babies,” she said. “I ugly cry, so it’s not going to be cute photos, but it’ll be a beautiful memory.”