Former child star Debra Byrne has thanked members of the public after her missing teenage grandson, Aaron, was found late on Monday.

The 19-year-old, who has special needs and requires medication four times a day, disappeared during a family outing in St Helena, Melbourne on Sunday afternoon.

Aaron resurfaced late on Monday after he presented himself at the Alfred Hospital in Prahran, 30 km from where he disappeared.

Byrne, 69, told Seven News that Aaron was exhausted and dehydrated, but was ‘doing well’.

‘Debra is incredibly happy and grateful,’ said Seven News reporter Kirsty Maher, after interviewing the relieved grandmother off-camera.

‘[And she] wanted to extend her thanks to everyone who looked for him on what has been a harrowing 28 hours of searching.’

Former child star Debra Byrne has thanked members of the public after her missing teenage grandson, Aaron, was found late on Monday

The 19-year-old, who has special needs and requires medication four times a day, disappeared during a family outing in St Helena, Melbourne on Sunday afternoon. Aaron resurfaced late on Monday after he presented himself at the Alfred Hospital in Prahran, 30 km from where he disappeared

The good news came after Byrne, who has raised Aaron since birth, made an emotional plea for help during an appearance on Seven News.

‘I worry that he’s very vulnerable, you know, he could get in someone’s car, but he’s not a child, he’s a man, but he’s a child, you know,’ she said.

Shedding tears, she added, ‘Oh God, I hated that he was in my care.’

Byrne and her grandson had joined family members to watch a hockey game at the Greensborough Hockey Centre in St Helena, 23 km from the Melbourne CBD, when he vanished.

Sharing details of his disappearance to Seven News, Byrne said that Aaron, who presents as an eight-year-old child, had become bored with the match.

He told his grandmother he was going to collect for recycling, and the last time she saw Aaron, around 1pm, he was carrying a full bag of cans.

She also said that her grandson, who had no money, no phone or food, had not taken his required medication since Sunday.

On Monday, the family learned that Aaron had checked into the Austin Hospital in Heidelberg.

But before Byrne could reach him, Aaron discharged himself around 9 pm.

Byrne was one of the original cast members of Young Talent Time, which debuted in 1971. She starred on the show for four years

Aaron was reunited with his family late on Monday, after he presented at the Alfred Hospital.

Byrne has raised Aaron and his older brother Oliver all their lives.

Her daughter Lauren is intellectually impaired and wasn’t able to consistently look after her children, so Debra was given full custody of the two boys.

Byrne was one of the original cast members of Young Talent Time, which debuted in 1971, and starred on the show for four years.

The performer had a mid-career surge of success with key roles in the Australian productions of high-profile shows such as Cats, Les Misérables, and Sunset Boulevard.

She had revealed her struggles with heroin and cocaine in her 2006 memoir Not Quite Ripe, while a sex tape featuring her and a former partner was leaked to the media in the late 1980s.