*Stars of NBC’s “Celebrity Apprentice” are sending well wishes and prayers out to fellow contestant Bret Michaels, who remains in intensive care following a subarachnoid hemorrhage (bleeding at the base of his brain stem), suffered late Thursday night.

The 47-year-old rocker is stabilized, but currently remains in critical condition at an undisclosed Victoria’s Secret model Selita Ebanks, who starred with Michaels this season on “Celebrity Apprentice,” called Michaels an “amazing guy, very strong and positive” and asked her Twitter followers “to keep the positive energy going.”

Holly Robinson Peete urged followers to “keep the prayer train rolling” for Michaels, and Sinbad also encouraged fans to “say a prayer” for the Poison frontman.

Sharon Osbourne wrote: “I’m thinking of you and wishing you a speedy recovery”, while both Summer Sanders and Ivanka Trump said that their “thoughts and prayers” are with the star and his family.

Wrestler Goldberg said, “Not really religious but please say a prayer.” Maria Kanellis wrote “Let’s all keep our prayers with Bret,” while Carol Leifer said: “We love you, Bret Michaels! Hoping and praying for you, buddy!”

The show’s host Donald Trump has also sent his well wishes to Michaels, saying his “thoughts and prayers” are with the star and his relatives.

Sunday night’s episode carried a post-script. Accompanying slow-motion footage of Bret carrying luggage across a tarmac, a voiceover said, “Everyone here at NBC wishes Bret Michaels a speedy recovery.”

A source tells People.com that a sudden excruciating headache – “llike [getting] hit in the head with a baseball bat over and over again” – prompted Michaels to call for an ambulance late Thursday.

Often referred to by doctors as a “thunderclap headache” because of the intensity and suddenness of the pain, such headaches are a tell-tale symptom of the kind of brain hemorrhage that Michaels suffered.

The Michaels’s source adds, “Bret is still in ICU. He still has the headache and is heavily sedated.”

A statement on his fan site noted that doctors are still searching for the source of the bleeding.