A Brisbane mother whose ''cheeky, beautiful and adventurous'' toddler was lost in a dam at the weekend had been picking up the pieces of her life after her husband died less than a year ago.

Two-year-old Michael McNamara was found at the bottom of a dam at South Maclean, south of Brisbane, at 3.45am on Saturday following a massive police search overnight.

On Saturday, a heartbroken family member told Fairfax Media the death of Michael, an only child, had shattered the family, which was still trying to come to terms with the death of Michael's father, Daniel, less than a year ago.

On March 19 last year, Mr McNamara was killed in a car crash north of Beaudesert, leaving behind Michael and his mother.

''He was an adventurous little boy and so cheeky … he used to giggle at us and make us all laugh just looking at his cheeky face,'' the family member said. ''He was beautiful, absolutely beautiful. We just can't believe it.''

Michael had been at home with his mother and her family at their property when it was noticed he was missing about 6pm.

They raised the alarm immediately, calling police, and the frantic search began.

''When we got the phone call, I have never heard [Michael's grandmother] so distraught in all her life,'' the family member said.

''That was heartbreaking. We were all sick with worry and no one has slept all night.''

A search party, which included police, the dog squad, fire brigade, members of the public and the State Emergency Service, trawled the acreage property well into the night.

The SES were sent home about 1am but the fire brigade stayed to drain the dam.

About 3.45am, Michael's body was found at the bottom of the dam.

His family were then delivered the news no one ever wants to hear.

''His mum can't speak to anyone right now, she's absolutely heartbroken. Just shattered,'' the family member said.

''She doesn't have the money to pay for the funeral … she didn't think she'd have to be having a funeral for her two-year-old son. I just want the best funeral for Michael that we can have and I want his mother to not have to stress about how to find the money while she's grieving so deeply for her baby.''

On the Queensland Police Service's Facebook page, thousands commented on the tragedy, many offering to help the family.

''We've been flooded with offers of help from across the world, with people wanting to donate money, food, flowers, coffee … they want to help in any way they can,'' the family member said. ''We're very grateful for any support.''

The family has set up a funeral fund through PayPal for anyone who would like to contribute. The email address is boo_81@hotmail.comAnyone wanting to deposit directly into a bank account can put money in BSB: 084385, account number: 147 933 147

View Larger Map