Looking relaxed, he insisted he would "very quickly" head to Cedars-Sinai Medical Center, where doctors put the 66-year-old singer in a drug-induced coma as Hallyday recovered from surgery to deal with an infection from an earlier operation.
The rocker, admitted to the Los Angeles hospital on Monday, had received the latest operation overnight Wednesday to Thursday due to severe lesions he suffered from a botched operation for a slipped disc last month at a Paris clinic favored by celebrities.
French music reality show presenter Nikos Aliagas accompanied the star's son, who wore a gray pair of jeans, a brown leather jacked and a baseball hat.
"I came to see my buddy," said Aliagas. "He's a good fighter."
Another French singer who traveled on the same flight, Charles Aznavour, declined to comment. He was scheduled to participate in an event for the Armenian community in Los Angeles.
Earlier, Johnny Hallyday's wife Laeticia went to the Lycee Francais in Los Angeles to attend a student show. Their daughter, Jade, attends the bilingual school.
While he has never been taken seriously abroad, Hallyday is by far the best known rocker in France, with a colorful rock 'n' roll lifestyle. He was born to a Belgian father in Paris but has homes in Los Angeles and Switzerland.
Known as the French Elvis, he has sold more than 100 million albums and played 45 major tours, selling out at stadiums.
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