(ABC NEWS) -- Three young women, who vanished a decade ago, were reunited with their families Monday after one of them was able to break free from the Cleveland home where they allegedly were held captive.
The shocking case of Amanda Berry, 27, Gina DeJesus, 27, and Michele Knight, 32, all of whom were abducted as long as 11 years ago, provides fresh hope for parents still grappling with their own child's disappearance.
Thousands of people go missing in the United States each year and many are never heard from again.
According to the National Center for Missing and Exploited Children, roughly 800,000 children are reported missing each year in the United States -- that's roughly 2,000 per day. Of those, there are 115 child "stranger abduction" cases each year, which means the child was taken by an unknown person.
Here are a few children and young adults who have been missing for years and who the FBI and local authorities are actively looking for. Read more to find out how you can help bring them home.
Missin Missouri Toddler Lisa Irwin, Now 2
There are still no leads in the case of Lisa Irwin, a 10-month-old baby who disappeared from her crib in the middle of the night in Kansas City, Mo.
Baby Lisa was last seen asleep in her crib when her mother, Deborah Bradley, said she checked on her at 10:30 p.m. on Oct. 3, 2011. The infant's father, Jeremy Irwin, discovered Lisa was missing when he arrived home at 4 a.m. the following morning after working an overnight shift. The parents immediately called the police.
Police were suspicious of the parents' story after their initial questioning. Bradley said that police accused her of having done something to her child, and also accused her of failing a polygraph test. No arrests have been made in the baby's disappearance.
Lisa has blue eyes, blond hair, is 30 inches long and weighs between 26 and 30 pounds. She has a beauty mark on her right outer thigh. She would have turned 2 on Nov. 11, 2012.
Missing Maine Toddler Ayla Reynolds, Now 3
The disappearance of Waterville, Maine, toddler Ayla Reynolds remains the largest police investigation in the state's history, according to a state official.
Ayla was 20 months old when she was taken from her crib the night of Dec. 16, 2011, her father told police.
Justin DiPietro said he put his daughter to bed, and awoke the next day to find her missing, according to police. Several other adults were in DiPietro's home that night, police said, including one non-relative. Ayla was living with her father while the girl's mother, Trista Reynolds was in rehab for substance abuse.
Although police have said they think Ayla was not abducted and that she is no longer alive, no one has been charged in her disappearance and the investigation remains "open and active," according to Department of Public Safety spokesman Stephen McCausland.
Ayla has blond hair and blue eyes. She was last seen wearing green, polka-dotted pajamas.
Missing Washington State Toddler Sky Metalwala, Now 3
There is still no sign of Sky Metalwala, and police have said his mother's account of what happened on the day her son disappeared is suspicious.
The FBI searched for the toddler, who has been missing since Nov. 6, 2011, after his mother, Julia Biryukova of Redmond, Wash., said she left him alone for an hour in a disabled car in Bellevue, Wash.
Biryukova told police she was driving with her two children when she ran out of gas on 112th Avenue. She and her then-4-year-old, Maile Metalwala, trekked about a mile to a nearby gas station, Northtowne Chevron Service, leaving Sky in the car, she said.
Biryukova did walk to the gas station that morning, police said, but she never bought gas there, and her story was "strikingly similar in nature" to a "Law & Order" episode.
Sky's father, Solomon Metalwala, who is separated from his wife, told ABC News in 2011 that he believed she was responsible for their son's disappearance.
No arrests have been made and Bellevue police consider the investigation ongoing.
Sky has brown eyes and black hair. He was last seen wearing a grey hooded sweatshirt, black and aqua blue sweat pants, and white socks. The toddler was 2-feet, 10-inches tall and weighed 28 pounds.
Missing Texas Baby Gabriel Johnson, Now 4
Gabriel Johnson, more commonly known simply as "Baby Gabriel," was last seen with his mother, Elizabeth Johnson, at a San Antonio, Texas, park at Christmastime 2009.
Johnson left Tempe, Ariz., on Dec. 18, 2009 with her 8-month-old son after the baby's biological father, Logan McQueary, 25, refused to let her adopt him out. Johnson was arrested in Miami, Fla., on Dec. 29, 2009 and Gabriel was nowhere to be found.
In October 2012, Johnson, 26, was found guilty of custodial interference and unlawful imprisonment stemming from the disappearance of the 8-month-old baby in an Arizona court. She was sentenced to five years in prison, followed by four years of probation.
Gabriel's whereabouts remain unknown. The San Antonio police department said the baby's disappearance case remains an "active and open" investigation, but no suspects have been named.
Missing Florida Girl Haleigh Cummings, Now 9
Haleigh Cummings was 5 years old when she disappeared from her father's Satsuma, Fla., home in February 2009.
The last person to see the curly, blond-haired girl was Haleigh's father Ronald Cummings's girlfriend, Misty Croslin, who was 17 years old at the time. Croslin told police she woke up in the middle of the night and Haleigh was gone.
Both Cummings and Croslin have denied all wrongdoing in the little girl's disappearance.
Ronald Cummings is currently serving a 15-year prison sentence for drug trafficking. Croslin, who later married, then divorced Cummings, is also in prison in connection with the same drug trafficking investigation that led to Cummings' arrest. She was sentenced to 25 years in 2010.
Putnam County Sheriff's Office considers Haleigh's disappearance case an active investigation.
Missing Oregon Boy Kyron Horman, Now 10
Almost three years after Kyron Horman disappeared from school, there is still no sign of the Portland, Ore., second grader and no arrests have been made.
The Multnomah County Sheriff's Office considers the case a "continuing investigation" and investigators are following up on leads as they come in.
Horman vanished from his elementary school on June 4, 2010, shortly after giving a science fair presentation on frogs. While investigators and volunteers initially scoured the neighborhood and dense forest surrounding the school, speculation turned to Kyron's stepmother, Terri Horman, who said she dropped him off at school that day.
Though Terri Horman has not been charged, a judge called her a "prime suspect" in the boy's disappearance during a hearing on Aug. 22, 2012.
Missing Washington Girl Lindsey Baum, Now 14
The disappearance of 10-year-old Lindsey Baum continues to affect her McCleary, Wash., community.
The sixth-grader disappeared the evening of June 26, 2009, as she walked home from a friend's house around 10 p.m. It was a 10-minute walk along a densely populated suburban street. She never made it home.
Lindsey has dark blond-brownish hair and brown eyes.
Missing New York Teen Brittanee Drexel, Now 21
Police are still seeking clues in the case of the New York teenager who disappeared April 25, 2009, while on a spring break trip.
Drexel, then 17, was last seen in Myrtle Beach, S.C., where she had traveled from her home in Rochester, N.Y., against her mother's wishes. Since then, no arrests have been made in connection with her disappearance.
Last seen leaving the BlueWater Resort, Drexel was captured on surveillance video visiting a group of Rochester-area men after having a falling out with the friends she'd originally accompanied to the popular spring-break destination.
Drexel has blue eyes and brown hair. Both her ears and her nose are pierced.
Missing North Carolina Girl Asha Degree, Now 22
It's been more than a decade since Asha Degree's family has heard from or seen their daughter.
The North Carolina girl disappeared on Valentine's Day in 2000, when she was 9 years old. Today, she would be 22.
Her father last saw her asleep in bed at 2:30 a.m., on Feb. 14, 2000. Then, a motorist claimed to have spotted her walking down North Carolina Highway 18 in Shelby, at 4 a.m.
Police said they believe Asha simply packed her backpack and started off down the road in the middle of the night. Several motorists passed her, but no one stopped to check on her. Eighteen months later, Asha's backpack was found wrapped in trash bags 26 miles away.
Baby Missing Since 1997 Sabrina Aisenberg, Now 15
What happened to Sabrina Aisenberg, a 5-month-old who vanished from her crib at her home in Valrico, Fla., in 1997, is still a mystery.
Sabrina's mother, Marlene Aisenberg, told police at the time that she had last checked on the baby at midnight on Nov. 24, 1997, but when she returned to her daughter's room at 6:42 a.m., Sabrina was gone.
Investigators initially accused Marlene Aisenberg and her husband, Steve Aisenberg, of lying about their daughter's disappearance, and charged them with conspiracy and additional charges in 1999.
In 2001, a federal judge ruled that investigators had lied when they sought permission to place wiretaps in the Aisenberg home. The charges against the Aisenbergs were dismissed after tapes recorded from the wiretaps were ruled inaudible by a federal judge.
The Aisenbergs maintain they had nothing to do with their daughter's disappearance.
Sabrina had brown hair and blue eyes as an infant.
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