Jimmy Kimmel shared a sweet tribute to late director Ivan Reitman through his 4-year-old son Monday.

The 54-year-old television host made his son, William John, wear a "Ghostbuster" outfit to pay a tribute to the director, who died Saturday at the age of 75.

"May the great #IvanReitman rest in peace," Kimmel captioned the Instagram photo. "As long as little boys believe in ghosts, your work will never be forgotten."

In the photo, the little one can be seen standing in the corridor of their house and looking up as he poses for the camera with a smile.

Fans took to the comments section to share their reactions.

"Jesus Christ man. You can't post a pic of your kid and start it 'Rest in Peace.' My heart was in my stomach," one person commented. Another person, in a reply to the user's comment, said, "I did the same thing my heart fell into my stomach."

"A sad day to loose another Ghost Buster great. On a happy note. Little Billy is an adorable Ghost Buster," a user wrote, while another commented, "He's so cute, he looks like you &your daughter looks like your wife. Both adorable."

Besides Kimmel, director Paul Feig and "Eternals" star Kumail Nanjiani also paid tribute to the late director Monday.

Reitman died peacefully in his sleep at his California home, the director's family said. The director's children - Jason Reitman, Catherine Reitman and Caroline Reitman – shared a joint statement Sunday to mourn the "unexpected loss."

The director shared his three kids with his wife, actress Geneviève Robert. The couple got married in 1976. The director was set to work on two projects, "Triplets" and "Summer of Love," at the time of his death.

Kimmel has been hosting the talk show "Jimmy Kimmel Live!" since 2003. He is also slated to host a TV special, titled "An Afternoon with SCTV," which is currently under post-production.

Kimmel also appeared on a podcast, "Just Headlines," on Jan. 27 and lent his voice to the animated comedy adventure "PAW Patrol: The Movie," which was released last August.

Jimmy Kimmel
Jimmy Kimmel’s son, Billy, is doing much better at the moment. Pictured: Kimmel speaks onstage at Los Angeles LGBT Center's 48th Anniversary Gala Vanguard Awards at The Beverly Hilton Hotel on Sept. 23, 2017 in Beverly Hills, California. Getty Images/ Emma McIntyre