Police have searched the area surrounding the 7700 block of Kite Street and found nothing. Mission RCMP say they don't suspect foul play.
But Rachel's family says they are worried because she has no history of running away.
"She was not stressed, she was not worried, she was looking forward to spending some down time with family," said Tina Pernosky, Rachel's aunt.
Pernosky's family says she is a frequent social media user, but her accounts have been quiet since she was last seen just after midnight on Saturday. Police found her phone at home and Pernosky missed her scheduled visit with her one-year-old son.
Nearly 2,000 people have joined a "Find Rachel Pernosky" Facebook page in an effort to co-ordinate search efforts.
Pernosky is described as five foot five, about 115 pounds, with long, dark hair. She was last seen wearing jeans and a purple hooded sweatshirt with a pink and white design on the front.
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