THE voice of the campaign to find William Tyrrell has urged people to think of the missing child on Australia Day.
Tuesday marks 501 days since William was last seen playing in his grandmother's front yard at Kendall.
The Where's William? campaign's Hetty Johnston said those with even the "most minuscule" piece of information must contact police.
"They might not think it matters, but it might just be the missing piece," Mrs Johnston said. "They might think it's irrelevant but if there's anything you know, please come forward."
Echoing comments from Detective Inspector Gary Jubelin, Mrs Johnston said police "are working through an enormous amount of information".
"But there is still information missing," she said.
Australia Day will be 501 days since the Tyrrell family experienced the "indescribable pain and sheer panic" of realising their son was gone, Mrs Johnston said.
"If a child goes missing for a split second in a shopping centre, a parent's heart goes into their mouth.
"The family have been living with that feeling for 501 days.
"We just can't tolerate that fact."
Tuesday also marks the 50th anniversary of one of Australia's most infamous child abduction case, the disappearance of the Beaumont children in South Australia.
"It is beyond the imagination of most of us that this could happen again and that people are staying silent," Mrs Johnston said.
She said Australia Day is a time to reflect on what is great about the nation and what needs to be better.
"As a society we need to make it clear that in Australia it's unacceptable to hurt children, that it's unacceptable that children may not be safe when playing in their own yard.
"What is not great is that fifty years-on since the Beaumont children's abduction, William, a beautiful little boy could still be abducted and the person or persons who know something about his disappearance can still remain silent.
"On Australia Day we must say that it's unacceptable to abduct a child and unacceptable for those who know something to not come forward, to not make the call that might help find William and bring him home."
Please contact Crime Stoppers on 1800 333 000 if you know anything that might help.
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