Christopher was admitted to a medical centre after breaking several bones and suffering a collapsed lung while surfing in Malibu last weekend, reports TMZ.
Schwarzenegger's son remains in an intensive care unit as of this morning, but sources told the website that the boy's condition has greatly improved in recent days.
Former California Governor Schwarzenegger, his estranged wife Shriver and their children have spent time together at Christopher's bedside since the accident.
Shriver filed for divorce from Schwarzenegger on July 2, weeks after the Terminator star admitted to fathering a love child with a member of his household staff.
Schwarzenegger's attorneys have officially asked a judge to deny Shriver's request for spousal support.
