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A leg injury may have led to a tragic set of circumstances in which a woman died suddenly and suffocated her baby son while breastfeeding.
Irene Rachel Skurr, 36, was believed to be feeding 10-month-old Cameron John McDrury on Monday morning at her Lincoln home, near Christchurch, when she died of a pulmonary embolism from deep vein thrombosis, where a blood clot had lodged in her lungs.
Her sudden death had caused her to collapse on her son and suffocate him.
Police said there were no suspicious circumstances and called it a "tragic and freak accident".
Deep vein thrombosis is commonly associated with long periods of inactivity, such as travelling on long-haul air flights.
A clot, or thrombosis, develops in a deep vein, usually the leg.
It then breaks off and can travel through the body to the lung, where it becomes lodged and blocks blood flow.
The Herald understands Ms Skurr had suffered a leg injury before her death that affected her mobility.
One relative said Ms Skurr had suffered a broken leg.
Police were called to Ms Skurr's home just after 8am on Monday and she and her son were both dead.
It is understood Ms Skurr's partner, Stephen John McDrury, the father of Cameron, was not at home when the tragedy occurred.
A family member told the Herald the deaths were the "saddest thing that could have happened".
The couple were very private people, the relative said.
Police urged the media to respect the family's privacy.
Ms Skurr, an only child, was raised in the North Canterbury town of Oxford.
She is the niece of Janice Skurr, former mayor of North Canterbury's Waimakariri District.
She worked at the Hanmer Springs Thermal Reserve for several years.
In August, Ms Skurr posed while breastfeeding her son for a newspaper photograph to run with a story about a proposed law to protect women's right to breastfeed in public places.
Results of post-mortem examinations on Ms Skurr and her son were released by Christchurch coroner Richard McElrea yesterday with the consent of the family.
An inquest will determine the full circumstances surrounding the deaths.