A 17-year-old charged with the murders of a Brisbane couple killed in a crash on Australia Day won't face any charges relating to the death of their unborn child.
Kate Leadbetter was pregnant when she and her partner Matt Field were struck by an allegedly stolen car driven by the teenager in Alexandra Hills on January 26.
Police say legal advice shows they can't charge him with killing an unborn child in this case.
"We understand that this may be difficult for some to understand," Assistant Commissioner Brian Codd told reporters on Tuesday.
'But I can assure you that the death of baby Miles will not be overlooked and will be presented for consideration to the courts as an aggravating element of the murder charge that we have put forward relating to the death of his mother Kate."
As well as the murder charges, the teen faces eight additional charges including dangerous driving while under the influence of an intoxicant, failing to fulfil duties at the scene of a crash and wilful damage.
He allegedly ran a red light and deliberately collided with a truck at an intersection before the 4WD rolled and ploughed into the couple who were crossing the road.
Relatives and friends farewelled the couple and their unborn child, who they had named Miles, at a private funeral on Monday.
Their families thanked all those who joined them to say goodbye and the wider community for the support and compassion they received.
"To the first responders and police who looked after Matt, Kate and Miles, and who have supported our families throughout this difficult time, words cannot express the depth of our gratitude for the way you have cared for each and every one of us," the family said in statement.
"Our families need time together to grieve. Our hearts go out to everyone missing them today, and we thank you for honouring their memories with us."
The teenager is being held in custody and will appear in Brisbane Children's Court on February 15.