"When she wasn't home by 10, I started to get nervous," Baum said, adding that 10 p.m. is the curfew for her children.
She began calling Lindsey's cell phone, only to find that her daughter had left it plugged into the charger. Initially thinking that her daughter must have met up with friends in the neighborhood, Baum set out on foot to find her.
But there was no sign of her. Eventually, her friend's parents joined the search by car. Baum even let her daughter's beloved German shepherd, Kadence, off its leash in hopes the dog would help find her. Finally, around 10:45 p.m., Baum said she called the police.
At the time, Scott said there were a few businesses located just off the street Lindsey would have used to get home, and while the girl did not appear in any of the videos, police received clues about who was in the area at the time she disappeared.
Scott said witnesses were able to put Lindsey within a couple of blocks of her house just after 9:30 p.m. The last person reported to have seen her, he said, was a neighbor on her way to work.
Baum described her daughter as outgoing, talkative and mature for her age. She loved to read and write, and had big plans for her future.
"She insisted when she grows up she's going to be an author and an illustrator and a veterinarian," Baum said.
Lindsey was 10 at the time she disappeared, and her mother said she was looking forward to celebrating her 11th birthday July 7.
At the search headquarters Friday, Baum told ABC News Seattle affiliate KOMO-TV that she became hopeful after learning police have a person of interest.
"I'm hoping they'll find her and give her back," she said.
Volunteers from McCleary and all over the region came to join the most recent search, which began Friday and continued through today.
"I can easily imagine how how hard it is, and this is the least I can do," Jen Page, a mother who drove 90 miles to help look for Lindsey, told KOMO-TV.
Scott said that though police have kept their efforts separate from the volunteers', investigators welcome the help.
"We're encouraging everyone, hunters in the woods, to have their head on the swivle to look for evidence of Lindsey and her disappearance," he said. "We're at the same time continuing our criminal investigation."