(WGHP) — Celebrities are reacting across social media to the death of Betty White on Friday.

The iconic actress and comedian died, just weeks before her 100th birthday, according to her agent.

William Shatner and George Takei, who played Captain Kirk and Hikaru Sulu on “Star Trek” respectively, shared messages of condolence.

LeVar Burton, who starred in Star Trek: The Next Generation as Commander Geordi La Forge and has recently appeared on “Jeopardy!” said “we have lost one of the best humans ever!”

Actor Ryan Reynolds had a lighthearted “feud” with Betty White over tabloid headlines.

“The world looks different now. She was great at defying expectation. She managed to grow very old and somehow, not old enough. We’ll miss you, Betty. Now you know the secret,” Reynolds said.

Henry Winker, most well known for his portrayal of Arthur “Fonzie” Fonzarelli on “Happy Days,” said he is thankful for Betty White’s humor.

Ellen DeGeneres also posted on Friday, saying she’s grateful for every second she got to spend with Betty White.

Actresses Viola Davis and Reese Witherspoon also took to Twitter to share messages of remembrance.

“Even though Betty was about to be 100, I thought she would live forever,” her agent and close friend Jeff Witjas told PEOPLE in a statement on Friday. “I will miss her terribly and so will the animal world that she loved so much. I don’t think Betty ever feared passing because she always wanted to be with her most beloved husband Allen Ludden. She believed she would be with him again.”

White was best known for her work on sitcoms, including her Emmy-winning portrayals of Sue Ann Nivens on “The Mary Tyler Moore Show” and Rose Nylund on “The Golden Girls.”