A father and son killed while walking to get ice cream from a local service station have been identified.

Braiden Timmins, 33, and his four-year-old boy Hendrix were allegedly struck by a ute on Green Rd at Regents Park in the city of Logan, south of Brisbane, just after 11am on Sunday.

WATCH THE VIDEO ABOVE: Father and son died after being struck by ute

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They were treated at the scene for life-threatening injuries but could not be saved.

The driver of the white LDV dual cab ute, Trevor William Galbraith, 41, from Regents Park, was not injured.

Galbraith was arrested at the scene.

Police have taken the rare step of charging him with two counts of manslaughter, rather than dangerous driving causing death.

The latter carries a maximum sentence of 10 years in prison, whereas the former carries a life sentence.

Footage from the scene showed a broken children’s bike lying on the footpath.

“My grandson’s mother... she’s grieving like you wouldn’t believe,” Hendrix’s grandfather Pete Geary said.

“He was a beautiful little boy.

“Hendrix was a very, very lovable child, very cheeky little boy.”

The forensic crash unit is investigating whether drink-driving was a factor.

Queensland Police assistant commander Matt Vanderbyl said the case was “tragic”.

“Those of us with young children, as many of us, saw that story last night and just went ‘what unimaginable horror’.”

Logan Council has just finished reviewing Green Rd.

The speed limit is set to drop from 70km/h to 60km/h. The road will also be resurfaced next year.

Galbraith didn’t apply for bail on Monday.

He will remain in custody until his next court appearance in later October.