AN ANGRY mother has sought legal advice after her seven-year-old son was "scarred for life" climbing the HMAS Brisbane memorial at Alexandra Headland.

A deep, red angry gash across seven-year-old Dré Conquest's forehead shows just how severe the accident was.

"If he hadn't put his hands up when he fell he could have died," his mum Elise Conquest said.

She was picnicking with friends at the popular site on the weekend and Dré was climbing the wall of the memorial when the accident happened.

"He was walking over it like a bridge. In the centre is the plaque and he stepped over it to not tread on it," Ms Conquest said.

"He fell back on the grass and the 20.7 kilogram plaque fell on his head."

Luckily Dré put his hands up to protect himself from the full brunt of the injury.

He was rushed to hospital where x-rays showed his head was not fractured. But he has a 10 centimetre long gash on his forehead which Ms Conquest believes will be there for the rest of his life.

Ms Conquest is angry that the plaque, which she weighed with a scale to prove it was 20.7kg, was not bolted in.

"It appeared to have been put on with some kind of plaster," she said.

Ms Conquest has sought legal advice with a prospect of claiming for medical costs as well as extra potential costs.

"The biggest thing is that he is alive, but if he hadn't protected himself and put his hand up it could have been a very different story right now,'' she said.

"He will be spending months regaining his muscles. He is a sporty kid and will have to be out of contact sport for a few months.

"He has got until he is 18 to make a claim as there could be ongoing things, such as constant headaches.

"Immediately it is more upsetting that I may have to miss out on work. It is a financial loss at the same time."

The council spends $2.28 million on its public liability insurance policy to protect itself from compensation claims.

A council spokesman said claims were referred to its insurer, which settled claims and the council was responsible for an excess which varied from $2500 to $15,000.

The spokesman said a regular inspection program was in place to identify risks and where maintenance and replacement was needed to protect community assets like the HMAS Brisbane memorial.

The plaque has been collected from the site and will be inspected before being securely fastened once an investigation has been completed.