Rolf Schumacher, who started his son's career in karting when Schumacher was aged four, arrived yesterday afternoon at the CHU hospital in Grenoble, France, where the seven times former world champion is in a critical condition.
Doctors say the next 24 to 48 hours will be decisive in his survival fight.
The star's wife, Corinna, 14-year-old son Mick - who was skiing with his father when he struck his head on a rock on Sunday - and daughter Gina-Marie, 16, have reportedly left him with lucky charms they hope will bring him good fortune.
Late on Monday, doctors operated on him to remove a brain clot after his condition had stabilised.
It aimed to treat the effects of internal bleeding within Schumacher's skull, which if left unchecked could have had catastrophic consequences for Schumacher.
"The situation is more under control than yesterday but we cannot say he is out of danger," Jean Francois Payen, head anaesthetician, told a news conference.
"We have won some time but we must continue an hour-by-hour surveillance... It is premature to speculate on his condition," he said, adding that Schumacher was still in a critical state and suffering from severe lesions and contusions.
Emmanuel Gay, head of the hospital's neurosurgery service, said the operation carried out had successfully removed a large hematoma from his brain.
"It was larger and more accessible (than others).
"We judged we could remove it without taking any risks," Professor Gay said.
He said the operation was designed to reduce, within Schumacher's skull, the pressure on the brain.
Profesor Payen said the medical team in Grenoble had discussed the operation with Schumacher's family. He added that his condition was still too fragile to consider transferring him to another hospital.
Schumacher is under the care of Professor Gerard Saillant, a brain and spinal injury expert who is also president of the International Automobile Federation (FIA) Institute. Professor Saillant said it was impossible to say how Schumacher's condition would progress.
Meanwhile, Schumacher's spokeswoman Sabine Kehm has revealed a journalist was removed from the hospital after attempting to gain access his room dressed as a priest.