BOSTON -- Sen. Edward M. Kennedy's son Patrick remains hopeful that his father will be able to "beat" the cancer that now threatens his life.

"He's comforted by the fact that his dad is such a fighter, and if anyone can get through something as challenging as this, it would be his father," his spokeswoman Robin Costello said Tuesday.

Kennedy, who represents Rhode Island in Congress, has been visiting his father regularly since his admission to Massachusetts General Hospital on Saturday.

"He's hopeful that his father is going to beat this and be back at it. This is definitely a medical challenge that his dad can get through," Costello said.