Dr James Gakara and his two children, five-year-old Dylan and three-year-old Hailey, have been buried in Nakuru.
The father and his two children were laid to rest at their Mbaruk home.
Dozens of mourners gathered in the sleepy Muhereshwa village in Mbaruk to pay their last respects.
Dr Gakara, 54, died on September 22 while receiving treatment at the Nakuru Level Five Hospital where he was taken after he was found unconscious in his house.
The children were found dead in their bedroom.
Police said Dr Gakara injected his two children with some unknown drug before injecting himself with the same substance.
A post-mortem on the remains of Dr Gakara revealed that he died as a result of ingesting an unknown substance.
Dr Titus Ngulungu, the government pathologist who conducted the exam at the Nakuru Level Five Hospital mortuary on Friday last week, reported traces of drugs in the body and the presence of injection marks on one of the arms.
"As a result of my examination, I have formed the opinion that the cause of death was a foreign substance suspected to be medicine,” Dr Ngulungu said, noting, however, that the type of substance was not immediately clear.
A post-mortem on the bodies of the two minors was conducted on Sunday last week at the Nakuru County morgue, with detectives collecting samples for further analysis as it did not show the exact cause of death.