A toddler was sent home twice by doctors who failed to spot his

broken arm.

Health managers today apologised and launched an investigation into the blunder.

David Miller's mother, Stacey, was convinced her three-year-old son had seriously hurt himself when he tumbled down a flight of steps at Brighton Marina.

But when she rushed him to the Royal Alexandra Hospital for Sick Children in Brighton on Sunday she was told there was nothing wrong and advised to keep an eye out for signs of concussion.

The next evening, with David still complaining, she took him to the city's out-of-hours BrightDoc service. They also sent him home, suggesting Ms Miller visit her GP the following day.

Only then was an X-ray ordered which revealed a break in one of the bones in David's right forearm.

Today David is back home looking forward to spending the next month, including his fourth birthday, wearing a bright red plaster as the fracture heals.

Ms Miller said: "We'd been down at the dodgems and were on the steps. I took my eye off him for two seconds and he slipped and fell.

"I was really worried about him so I took him straight to hospital.

"I knew there was something wrong - his arm just didn't seem right.

"David didn't seem to be in a lot of pain with it but I just wasn't happy.

"After we were sent home twice I went to my GP and insisted David was sent to the hospital for X-rays.

"I spent the day there while he was checked out and in the end they found out he had broken a bone and bent another one."

Ms Miller, 21, said: "Doctors told me the location of the break was in a part of the arm which is not used a lot.

"But that is not really the point. When I took David to hospital the first time he should have been X-rayed and checked out.

"If they had spotted his injury sooner then they could Injured boy sent home have started his treatment sooner.

"Surely if a little boy has a bad fall and has pains in his arm he should automatically go for an X-ray?"

Ms Miller, who works as a care assistant and lives in Findon Road, Brighton, plans to write to the hospital to demand an apology and ask what went wrong.

She said: "I can't believe this was not picked up at the start and that I had to push and insist that he got checked up.

"If I hadn't insisted then it might have caused all sorts of problems later on.

I'm really angry."

A spokeswoman for Brighton and Sussex University Hospitals NHS Trust said: "We regret that it appears the fracture in David's arm was not identified in the children's hospital on Sunday.

"We are holding an investigation to find out what happened and extend our apologies to the family."