A neighbour, Joseph Kamau, said Mukundi could not stand having people he didn't know enter his compound.
"He would shout from the balcony, 'Unaingia huku ni kwa mamako'? He would then chase you away without listening to anything," Kamau said.
Kamau, however, said Mukundi loved his mother so much that she would visit her often. She stayed in Ruiru, Kiambu.
There have been claims that Makundi also had a wife and two children who live in Europe.
The 42-year-old was a licensed gun holder and worked with insurance companies where he bought written-off cars and sold spare parts at their shop in Mlolongo.
His wife worked at the shop. She is said to have been having an affair with an employee.
The body of the businessman was found alongside that of his wife hours after the incident had happened, having shot her three times in the head before turning the gun on himself.
They had been inside their bedroom, which had been locked from inside.
The two had separated for two months before they met on Monday. They were found dead on Tuesday evening. Philomena had three gunshot wounds to the head and Mukundi one self-inflicted gunshot wound to the head too.
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