Paul Deya, now 32, murdered his son, in their home on the Lynton Estate in Southwark on 23 November 2009.
He was also found guilty of GBH with intent against his wife on the same date. The court heard how in the months before the toddler’s death, the relationship between Deya and his wife had deteriorated causing them to agree a period of separation. It was agreed that Deya would move out, leaving his wife with the children in the family home.
On the day of the murder his wife gave their children breakfast before leaving them at home with their father whilst she went to work.
Between 16:00 and 16:30hrs she received a text from her husband which read "I wish you all the best."
She drove home where she found the front door had been bolted from inside. Receiving no response at the door, she climbed through the bathroom window into the flat which was in darkness.
She walked to the doorway of her son’s bedroom where she saw him lying on the floor in a pool of blood.
Deya was also lying on the floor, bare-chested. When he saw his wife, he grabbed a kitchen knife which was by his side and chased her out of their flat.
He caught up with his wife on some external stairs where he slashed her ear causing a deep cut.
The woman continued to run down the stairs but Deya returned to the flat and shut the door behind him.
The first police officers to arrive at the scene found a woman suffering from shock. She told them her husband had killed their children.
The officers took the keys to the flat from and let themselves in. Inside they found the lifeless body of the little boy; he had been stabbed in the abdomen and throat. In the master bedroom they found the couples other child unharmed.
Deya was taken to hospital and treated for self-inflicted stab and slash wounds to his neck and abdomen.
Officers examining the flat later found a hand-written note from Deya to his wife in which he made various accusations towards her. The note also set out the disposal of his property and instructions for the burial of his body, and those of his children.
Detective Inspector Keith Braithwaite, Child Abuse Investigation Command, said: "I am pleased that the jury have found Paul Deya guilty of the murder of his son today.
"He attempted to justify his actions by making accusations against his wife and blaming failings in their marriage for the course of conduct he undertook.
"I would like to thank the victim’s mother for her courage and dignity throughout what was a complex investigation."
Deya will be sentenced at the Old Bailey on 4 February.