WHEN investigating police asked for a serious photo of missing person Sandrine Jourdan, the family struggled to come up with one where she was not smiling.
"She was bubbly, friendly ... she could make friends with absolutely everybody," Sandrine's sister Christine Day said.
"Her laugh was so infectious - her friends wanted to be around her all the time."
Sandrine disappeared in the blink of an eye.
She had been visiting a friend on Tomlinson Rd, Caboolture, on July 13, 2012, when, after the friend said he needed to take his son to motocross, she decided to walk to the front of the property and open the gate.
A cold night, Sandrine had borrowed a jacket from her friend.
That jacket was the last trace of the 38-year-old ever found, left on the front fence of the property.
After much investigation, police have told Sandrine's family her disappearance was likely a walk-off or a suicide.
But the family refuses to believe the loving mother of three would simply abandon her children.
"Knowing Sandrine, we know she wouldn't stay away from her family and kids," Ms Day said.
"I believe foul play was involved."
Ms Day said the night Sandrine went missing, residents on Beerburrum Rd heard a woman's "chilling" screams coming from bushland.
Two men were later seen leaving the area.
Police have searched the bushland, including a small dam, using dogs, SES volunteers and divers, to no avail.
They have interviewed ex-partners, friends and members of a drumming group Sandrine was part of.
However, no charges have ever been laid.
Sandrine's family continues to search for clues as to what happened to her, employing psychics and regularly conducting their own searches.
But the seemingly endless investigation has worn them down, and Ms Day said Sandrine's two brothers, four sisters and her mother had struggled since her disappearance.
"It's caused mum a lot of stress, caused her to blame herself," Ms Day said.
Sandrine's mother was the last family member to see her, having dropped her off at a friend's house the morning she went missing.
"It doesn't matter what we say, I think mum will still blame herself for dropping her off," Ms Day said.
Last week was National Missing Persons Week, and Sandrine's family are urging anyone with information about her disappearance to come forward.
"Everything doesn't add up," Ms Day said.
"There's no way Sandrine would stay away from her friends, family and kids."
Do you know something? Call Crimestoppers on 1800 333 000.
If you're experiencing hardship, contact Lifeline on 13 11 14.
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