Tragic Tyrell Cobb's mum smoked dope daily, says ex

The ex-boyfriend of a mother accused of fatally injuring her son says she used to smoke marijuana daily and would often “lose patience” with her child when she was sober.

Matthew Scown told court Heidi Strbak was often “frantic and panicking” when she had not smoked marijuana.

The court has also been shown photographs of a bong pictured in the family’s unit.

Heidi Strbak has pleaded guilty to the manslaughter of her son Tyrell Cobb but denies allegations that she caused the four-year-old’s fatal injuries.

The 34-year-old says she is only guilty of failing to provide medical help.

Mr Scown was last month sentenced after pleading guilty to the manslaughter of Tyrell.

He was filmed by 9NEWS grinning and then laughing at a cameraman as he left court after his punishment.

Tyrell died in hospital on May 24, 2009, on the Gold Coast after an ambulance was called to his apartment after Mr Scown noticed he was vomiting, unconscious and had “gone all limp”.

Ms Strbak’s defence team has pointed the finger at Mr Scown, who was Strbak’s boyfriend at the time, listing examples of times that Tyrell allegedly complained that the man had harmed him.

The hearing is a contested sentence, which will run similar to a trial.

Justice Peter Applegarth will hear evidence from witnesses before making a determination on what sentence to impose.

The maximum sentence for manslaughter is life imprisonment.