On school days, he gets up at 5am and prepares breakfast and lunch.
In the evenings, he rushes home to empty the bedpan.
And Xu Jiahao is just 13 years old.
The boy from Yiyang county in Jiangxi has touched thousands in China with how devoted he is to his father.
Mr Xu Jiangshan, who is in his 40s, lost both his legs and his right hand to vasculitis (a condition where the blood vessels are inflamed) over three operations in 2008, 2012 and 2013.
The only limb he is left with, his left hand, has just four fingers.
Life with his son is a struggle. Life without him would be impossible.
Jiahao refused to abandon his father even after his mother divorced Mr Xu and left the family following the first operation.
She has since remarried and did not seek custody of Jiahao.
After the Chinese media reported about the pair in April, several families approached Jiahao, offering to adopt him.
But he has turned down all the kind offers, he says. Even when his dad wishes his son will go.
Mr Xu says: "It is for my child's own happiness and his future. Another family will be able to provide my child with what I cannot do in this life."
But Jiahao remains adamant in his decision.
He says: "I will not leave my father and our home no matter how tough life is, not unless my father can come with me."
In a telephone interview with The New Paper on Sunday, both father and son take turns to speak.
There is light bantering as they pass the mobile phone to each other, often prompting: "Okay, this question you have to answer."