A former Canadian soldier who killed three family members and himself in 2017 complained about repeated head injuries soon after he left the military in 2015, an inquiry heard.

The inquiry is investigating why Desmond killed his wife, mother and 10-year-old daughter before killing himself in their rural Nova Scotia home in 2017.

During the first phase of the provincial fatality inquiry, which started last year, the hearings focused on the involvement of police and provincial health and firearms officials.

Testimony at the Desmond Fatality Inquiry will now shift focus to the medical treatment Desmond received while still in the military.

The inquiry heard for the first time from Lionel Desmond's immediate family, including Shanna Desmond's parents and her younger brother.

Orlando Trotter described how he and Desmond took part in intense firefights with the Taliban on an almost daily basis over a seven-month period.

The inquiry heard testimony from Albert (Junior) MacLellan, a retired warrant officer who was called in to help the grieving families.

The fatality inquiry has heard that the former Canadian soldier was suffering from severe post-traumatic stress disorder and a possible traumatic brain injury.

The former Canadian soldier was suffering from severe post-traumatic stress disorder and a possible traumatic brain injury when he was released from the military in 2015.

There will be restrictions on in-person access to the inquiry as a result of the pandemic. However, the court has now confirmed that proceedings will be livestreamed online.