Sir Frank Williams is in hospital recovering from pneumonia, the Williams team confirmed on Friday.
Williams, whose eponymous team has collected seven drivers' and nine constructors' titles, has maintained a constant presence in the paddock since his team's 1977 debut and continues to retain a majority share despite delegating day-to-day duties to his daughter Claire Williams.
However, with both Sir Frank and Claire missing from the paddock for some races now, Williams chief executive Mike O'Driscoll revealed the 74 year-old was taken ill at the Italian Grand Prix in September.
Diagnosed with pneumonia, Sir Frank remains in hospital almost two months later, but O'Driscoll says he is making a 'slow recovery'.
"He's had a tough time in hospital, he's contracted pneumonia. He is making a recovery, a slow and steady recovery. We hope to see him back at Grove (the team headquarters) very soon. We all know how determined he is."
"We expect Claire to be back at a race, she's wanted to stay close to home, close to Frank but...we stay connected. She's part of everything that happens on a minute by minute and day by day basis," he added.
Claire Williams is expected to be seen at Thursday's presentation of Williams' 2017 F1 drivers, where 18 year-old Lance Stroll is set to be revealed alongside a re-signed Valtteri Bottas.