Retired soccer player Brad Knighton's family has suffered a tragic loss.

The former New England Revolution goalkeeper's daughter Olivia Knighton died at age 11 in a boating accident near Myrtle Beach, South Carolina July 19.

"There are no words to express the depth of our profound grief and sorry in this moment," read a message posted on Brad's Instagram July 20. "Our family is still in shock at the sudden and tragic loss of our beautiful and brilliant daughter, Olivia, to an unfortunate boating accident yesterday. We are all still in disbelief that her bright and pure light was taken away from us so suddenly. Somehow, we will get through this together as a family."

In addition to her dad, who retired from professional soccer in January after 16 years, Olivia is survived by her mother, Britney Knighton, and younger brothers, Owen Knighton, 9, and Brooks Knighton, 5.

"Olivia loved soccer and the Revolution with all of her heart," the message continued. "Our family always felt your support behind us during my career. We will need you and your prayers with us now more than ever. We love you, Olivia. Brad, Britney, Owen, and Brooks Knighton."

The South Carolina Department of Natural Resources said in a statement that the accident is under investigation. "Initial information indicates that a 23-foot boat carrying 12 people was traveling on the Intracoastal Waterway in Little River," the group tweeted July 20. "The boat was rocked by a large wake caused by another boat, resulting in nine of the 12 occupants going overboard."

The message added, "An 11-year-old girl was struck by a propeller and later died of her injuries. Nobody else was injured in the incident."

Following the tragedy, the New England Revolution also issued a statement expressing their condolences.

"The entire New England Revolution community is devastated to learn of the Knighton family's tragic loss," the team said on Instagram. "Olivia was a bright and shining light who was a beloved presence around the Revolution throughout her entire life, always bringing a warm smile and laugh to Gillette Stadium and our training facility when she would visit. Her sudden loss leaves a profound hole in our hearts."

The message continued, "The club sends its deepest condolences to Britney, Brad, Owen, and Brooks, and we will be there to support the Knighton family in every way possible."

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