THEY were making jam drops in class and Marilyn Wallman seemed unprepared. She’d left her cookery book at home.

She hadn’t brought the instructions and hadn’t prepared for the class.

Her exasperated teacher chastised her and sent her to the back of the room. But the unflappable Marilyn was not concerned.

Later, as students pulled trays, bowls and ingredients from cupboards, Marilyn, still sans recipe, came to join in. She mixed and stirred, poured and sprinkled. After an hour or so, she presented a startled teacher with the most perfect tray of jam drops that day.

Marilyn Wallman already knew how to cook. She’d learnt from her mother, Daphne.

This is a new memory for Marilyn’s brother, Rex, told to him by an old school friend of his sister’s. His own memories of her are few. He thinks pain and time have blocked them.

It’s the memories of their last day that stay with him.

It was March 21, 1972, and 14-year-old Marilyn grabbed her bike and rushed off for school, excited that it was sports day. Her brothers, David and Rex, left 10 minutes later, pedalling along Wallmans Rd past the canefields towards Mackay’s Rural Youth Hall, where the school bus stopped.

They were less than 200m from home when they saw her bike, lying on its side, the front wheel still slowly spinning.

“Our first thoughts were that she’d fallen off the bike and hit her head and she was dazed and wandered into the cane,” Rex said.

The boys shouted for her, and when there was no answer, they decided David would reach their mum the quickest.

“I sat there in the middle of the road waiting for them to come back. It’s while I was sitting there that I heard the noises and voices,” said Rex, who was eight at the time.

“It’s really hard to explain. It was like talking, but someone saying, ‘No, that hurts my legs’ – that sort of thing.”

Rex didn’t really recognise his sister’s voice but believes he was hearing the sound of Marilyn being kidnapped.

His mother and brother arrived soon after and they spread out, but none of them ever saw Marilyn again.

The years that followed were filled with thousands of leads, hopes, and dashed hopes.

In 1974, part of a skull was discovered in nearby Mirani. DNA tests positively identified it as Marylin’s.

In February, police excavated a Mackay backyard following a tip-off. Nothing of significance was found.

Rex said he was grateful his sister’s case was again being actively investigated after so many years.

“It was put away as a cold case and there was nobody looking at it,” he said. “Now we have a full-time detective working on it.”

He’s grateful for this because before a detective was put back on the case, Rex had been doing the work himself.

Like Daniel Morcombe’s father Bruce, Rex spent years going out to meet people who said they had information about his sister’s disappearance.

He’s grateful too for events like one held in July, when Marilyn’s old school friends got together and held a reunion in her honour. It gave him an opportunity to hear stories about his sister that he didn’t know.

He hopes that one day, someone will give police the answers they need.

“In those days, it was a very, very small community out here,” he said. “Somebody had to have seen something … or, at some stage of their life, told someone something.

“I always bank now on the fact that this person has to be (old) and may still be with us, or may not be with us. If they have passed on, people that know some information may now feel safe to come forward.

“Our main drive is to find Marilyn.”

On September 11, the Queensland Government announced a $500,000 reward for information leading to the closure of the Wallman investigation for a period of 12 months.

Crime Stoppers: 1800 333 000