PAWTUCKET, R.I. (WPRI) — Family and friends are mourning the loss of a brother and sister who were killed in a crash on I-95 Saturday.

Rhode Island State Police are still investigating the crash that claimed the lives of 33-year-old Tiffany Joslyn and her brother, 28-year-old Derrick Joslyn of Cumberland.

According to police, Derrick’s wife was driving in the high-speed lane on I-95 South in Pawtucket when another car moved into the lane, causing the Joslyn’s car to hit the Jersey barrier and roll over into the northbound lanes, where it was struck by a van.

Police said Derrick and Tiffany died at the scene while Derrick’s wife, two people in the second car and two people in the van suffered non-life-threatening injuries.

Tiffany’s friend, Gordon Simonett, said she was a public servant who resided in Arlington, Virginia.

“She just wanted to get things done and make life better for people – especially for people who didn’t have a voice in the process,” he told Eyewitness News over the phone Monday.

Simonett said he met Tiffany back in 2009 in the DC area. They formed a friendship through political activism. Simonett said Tiffany was very active in issues surrounding social justice, fairness and equality.

She was also a lawyer who worked for the House Judiciary Committee and helped Congressman David Cicilline’s office advance criminal justice reform.

According to Simonett, she had a smile that could brighten a room.

“She was just very focused on the positive, very focused on investing in people, investing in friendships,” he said. “We need more kindness in the world and we need more people in the world like Tiffany. It’s just tragic that we lost someone like her in the way that we did, a freak accident.”

The crash that killed Tiffany and her brother Derrick remains under investigation. To date, no criminal charges have been filed.