POLICE believe South Australian dad Damien Little shot himself and his two children before driving the family car off the wharf at Port Lincoln.
Autopsies on Damien Little and his sons revealed they had all been shot.
The car plunged into up to 30 metres of water after being driven off the wharf at high speed.
The development came as Mr Little's grieving wife and mother of Hunter and Koda, Melissa Little, released a statement.
She said her husband put his family first and loved his two children.
Police have confirmed they are investigating mental health issues as possible reasons behind the murder-suicide.
"Damien was my childhood sweetheart who became my loving husband," Mrs Little said.
"Damien valued and appreciated our close-knit family ... we were his whole world. He spent every hour providing quality time and teaching the boys how to live and grow.
"Damien I loved you so much you have left a huge hole in my heart, our memories I will cherish forever. You will not be forgotten.
"My wish is for Damien to be remembered as a well-respected and valued member of our family and our community.
"My two precious boys have left this world way too soon and my heart is broken.
"I will miss them and think about them each and every day. Their futures were full of endless possibilities.
"Koda had the biggest heart, so loving and caring. He always loved a hug, had so much enthusiasm and was a willing helper.
"Hunter was such a happy, content and smiling baby. His laughter was infectious and his cheeky little personality was just beginning to emerge."
A second statement from extended family members, including Ms Little, Dale and Debby Goldsworthy and Ken and Sue Little, thanked emergency services, Port Lincoln residents, the city's Mayor Bruce Green, South Lincoln football club and the Port Lincoln Ports Corporation for their support.
"We are never prepared to face such unexpected tragic events," it read.
"The outpouring of love, support, well wishes and offers of help from family, friends and community, is such a comfort at this sad time."
If you need help with coping phone Lifeline on 13 11 14.
*For 24-hour support phone Queensland's DVConnect on 1800 811 811 or Men's Line on 1800 600 636, NSW's Domestic Violence Line on 1800 656 463 or the national hotline 1800RESPECT (1800 737 732).
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