Years before aspiring to become a 2024 presidential candidate, Robert F. Kennedy Jr. embarked on a relentless pursuit for answers about his father's real killer, according to insiders who spoke to RadarOnline.com.

Robert F. Kennedy, a promising political figure, was brutally assassinated on June 6, 1968, after securing a victory in a critical Democratic primary. He was only 42 years old.

Sources reveal that RFK Jr. uncovered persuasive evidence suggesting a security guard at Los Angeles' Ambassador hotel might have played a part in his father's murder. The contention is that Sirhan Sirhan, the man convicted for RFK's assassination, may have had an accomplice, Thane Eugene Cesar.

"Law enforcement never seriously probed Cesar's involvement in my father's death," RFK Jr. stated in a pre-presidential campaign Instagram post, using social media as a platform to advance his theory that Cesar delivered the deadly shot.

Prominent pathologist Dr. Cyril Wecht echoed RFK Jr.'s sentiments, criticizing the police for a flawed investigation. Wecht, part of the Truth and Reconciliation Committee pushing for a renewed investigation into the murders of RFK and JFK, also hypothesized Cesar as a potential culprit, despite Cesar passing a polygraph test denying firing his weapon.

Cesar passed away in the Philippines in September 2019 at age 77, taking any undisclosed information to his death.

In his social media post, RFK Jr. delved deeper into his allegations against Cesar. He claimed that Cesar had positioned himself in the pantry while his father addressed the ballroom audience, thereafter guiding RFK towards Sirhan.

"Sirhan had already fired two shots at my father before being tackled. According to his account, Cesar was right behind my father, gripping his right elbow with his gun drawn when my father fell backwards onto him. Cesar's narrative of when he drew his weapon has changed multiple times."

RFK was hit by three bullets, including a fatal headshot. Despite Sirhan's .22-caliber revolver only holding eight bullets, eyewitnesses reported hearing a minimum of 13 shots, and bullet holes were discovered in a door frame and wall behind Sirhan.

A private investigator suggested that RFK's potential access to classified information about JFK's assassination, if elected, may have presented a motive for his murder.

Paul Schrade, also wounded on that tragic night, also suggested the possibility of a second gunman.

Earlier this year, Sirhan was denied parole for the second time, following an earlier refusal by California's governor to support his release.