This timeline comes from shmoop. I didn't know what chapter you're referring to, and I don't have time to skim through the entire novel right now.......
Eliezer’s father, at 50 years old, is older and weaker in body than his son. Eliezer’s father also becomes a target when guards want something (such as the gold tooth) from Eliezer, because Eliezer wants to protect his father.
When Eliezer’s father thinks he’s been selected to die, he gives Eliezer the only things of value he has left – a knife and a spoon.
Eliezer’s father thinks it best for Eliezer to leave the hospital, and be evacuated with the rest of the prisoners, when he hears the Russians are coming. He hopes it’s for the best but doesn’t know for sure.
As they march through the snow towards the next camp, Eliezer’s dad grows weaker and sicker. He almost dies on the last stretch of the trip, while on a train. Eliezer manages to wake him up in time to save him from being thrown out of the cattle car with the other corpses.
When they finally arrive at Buchenwald, Eliezer’s father is deathly ill. Fellow prisoners are mean to him, denying him food or beating him, as if they just want him to die. He hovers between life and death for several days, constantly asking Eliezer for water and calling Eliezer’s name.
At last a guard, angry, hits him on the head with a deathly blow. Slowly, Eliezer’s father dies, calling Eliezer’s name. It is January 28, 1945.