The victims are now resting on the fourth floor of SF General, in ICU. Doctors upgraded their conditions to stable, but there are still several challenges ahead for these two men.
"They're in good spirits and look fantastic. They have youth going for them," said Dr. Rochelle Dicker from San Francisco General Hospital.
It's been a trying 24 hours for the 19 and 23-year-old brothers from San Jose.
What started as a visit to the San Francisco Zoo on Christmas Day ended with the loss of their friend, 17-year-old -- Carlos Sousa Junior.
Authorities now know the tiger first attacked and killed Sousa before going after the brothers.
"They both had lacerations, lots of cuts due to the teeth or claws of the animal," said Dr. John Brown from San Francisco General.
The victims arrived at SF general 40 minutes after the first 911 calls went out, with deep wounds to their heads and upper bodies.
"I think they'll do well as far as scarring. I don't think they'll have lasting effects happily," said Dr. Dicker.
But specialists have two serious concerns: the first is the victims' mental health and their reaction to losing Sousa; the three came to the zoo together. The other concern involves infection.
"The big problems are infection and damage to tissues underlying the skin," said Dr. Brown.
Both brothers are getting high doses of antibiotics as a precaution. Even though their wounds may heal quickly, the bites could become infected and cause complications.
That's what happened to a North Coast man earlier this year, after a mountain lion attack.
"The infection was the hardest part, but I was unconscious then so the hardest part was really the fright," said Jim Hamm on April 11, 2007.
Doctors expect the victims will suffer from post traumatic stress. That's why watching and monitoring their condition is key.
Doctors first thought the victims could go home as soon as today. That has been changed to possibly tomorrow and it all depends on how well they do tonight.