A fertility doctor in Southern California has been charged with murder in the 2016 death of his wife, authorities said.

Eric Scott Sills, 54, who’s suspected of killing 45-year-old Susann Stephanie Arsuaga Sills on Nov. 13, 2016, was arrested Thursday night and is being held on $1 million bail, according to the Orange County District Attorney’s Office.

“We are happy there has finally been movement in Susann’s case. Obviously we are shocked that Eric has been arrested in her murder,” Cynthia Arsuaga, Susann’s stepmother, told The Daily Beast on Monday. “Right now we are trying to grief as a family as these wounds are now reopen, and we hope to find peace for Susann.”

Authorities have released few details in the case, including Sill’s cause of death, the motive behind the two-year-old murder, and what new evidence led to the doctor’s arrest.

The couple co-founded the Center of Advanced Genetics fertility clinic in Carlsbad, about an hour outside of San Diego. Eric Sills, who holds a doctorate from London’s University of Westminster and a medical degree from the University of Tennessee, served as the center’s medical director while his wife was the managing partner. The pair started the clinic together in April 2015, the center confirmed to The Daily Beast on Monday.

According to his company bio, Eric Sills practiced in-vitro fertilization in Europe and the U.S. and wrote multiple books, including Fighting At The Fertility Front—A Navigational Guide to Infertility for U.S. Military, Veterans and Their Partners.

“In addition to books, Dr. Sills has authored more than 100 peer-reviewed journal articles and has collaborated on the discovery of three previously unknown human gene mutations,” his online biography states.

Susann Sills, a Philadelphia native, received her MBA in international studies from the University of Miami in 2000. Together, the couple has two children, twins Mary-Katherine Estelle Sills and Eric Scott Sills II. The 54-year-old doctor also has two children from a previously marriage, Charles Alton Carmack Sills and Ann-Marie Carter Sills.

“Her sudden loss was a deep sorrow for the many friends, family, and patients to whom she had endeared herself during her love-filled life,” her obituary said.

According to users, the 45-year-old was a member of Patrick.net, a social forum where she posted under the pseudonym turtledove. In a thread posted soon after her death, one member, MMR, wrote that Eric Sills reached out to say she had died of an accident.

“I got an email from her husband today indicating that she had passed away,” the user wrote, adding that Sills said his wife suffered from “chronic migraines which kept her up.”

MMR also claimed that Eric Sills said his wife “fell down the stairs early Sunday morning,” an assertion that some found it hard to believe. In another post, MMR alleged that the mother of four had been cremated.

“I just find it hard to believe that someone as young as she was could sustain life threatening injuries falling down the stairs,” one wrote.

Sills’ attorney, Fred Thiagarajah, declined to comment on the case, saying that his team is “choosing to not speak about it until they have gathered more information.”

The Orange County Sheriff’s Office declined to release any details about Susann Sill’s death, as they have “passed off the investigation to the district attorney’s office.” The district attorney’s office also declined to provide further details on the investigation, citing “the sensitivity of the ongoing investigation.”

Sills is currently being held at the Orange County Correctional Facility.