Mr Khan told the jury during Hutton's trial that he had contacted Bradford social services once about the condition of Hamzah, but he was ignored.
He told the court he had separated from Ms Hutton after he was charged with assaulting her.
The jury heard he was initially stopped from visiting his former partner due to a court order, but he did start to go and see his son when they moved to a new home in Bradford in March 2009.
Details of a police interview conducted with Mr Khan recorded a year before Hamzah's death in 2009 were read to the court.
Mr Khan, who had been arrested on suspicion of violence towards Ms Hutton, told officers: "You've got to keep an eye on that woman.
"All I want you to do is get a doctor to check Hamzah, check how undernourished he is, check how neglected he is, see how he is."
A force spokesman said: "The interviewing officers had seen the children in their home five days previously when attending the initial incident and there was nothing that caused them concern at the time.
پاسخ با گفتآورد