The parents of the 20-year-old man involved in a high-speed crash that claimed the lives of Chief Superintendent Joanne Shanahan (nee Panayiotou), 55, and Tania McNeill, 53, released a statement on Friday.

They said that it was “impossible to find the words to describe the depth of (their) despair” regarding the accident caused by their son, Harrison Kitt.

Kitt was also seriously injured in the accident and had also been seriously injured in the three-car crash at an Urrbrae intersection on Saturday afternoon.

In their statement, Andrew and Kathy Kitt said:

“We have only known our son, Harrison, to be a kind, responsible and compassionate young man.

“We don’t understand what triggered this incident but we had been worried about Harry’s mental health in the few days leading up to it.

“Harry was not himself and his behaviour had become so uncharacteristic that just a short time before the accident one of his friends had called us to express his concerns for Harry’s welfare.”

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The statement expressed the understanding that the “family, friends and colleagues of the occupants of the other vehicles, all want to understand why this has happened,” he said.

“We expect that it will be some time before the questions on everyone’s minds can be answered.”

The parents paid tribute to the victims of the crash and understand that nothing can “bring back the two lives that have been so tragically lost.

“There is no un-doing what has happened and the weight of that recognition is almost impossible to bear.”

Investigations into the collision are continuing.

Call Lifeline on 13 11 14, Beyondblue on 1300 22 4636, or Kids Helpline on 1800 55 1800 if you or anyone you know is suffering from Depression.