NASHVILLE, Tenn. (WKRN) — As the new year approaches, it marks a grim milestone for many Tennessee families hoping to one day see their children again.

As of December, there were at least 30 children whose whereabouts were still unknown. Some like 17-year-old Olivia Carroll were reported missing as little as a week ago, while others have been missing since 2008, according to the Tennessee Bureau of Investigation.

Carlos Edwardo Simon, 6, and Maniol Baldimir Pena Castro, 1, were reported missing from Knoxville on May 28, 2008. According to the TBI, the two young boys were last seen with their non-custodial mother, Leticia Castro. The case is believed to be a family abduction.

Those missing may be in a variety of circumstances, including parental abductions, children considered at-risk, those who’ve left home on their own and other types of cases in which the TBI said publicity may prove helpful in locating them.

However, the children listed by the TBI only represent a portion of kids missing in the state. In a previous interview, Shelly Smitherman, TBI Assistant Special Agent in Charge, said an average of 500 to 600 kids under the age of 18 go missing each month in Tennessee.

For at least three families, the month of December marked a full year since they last saw their children. Carlos Sagastume-Vallecillo, 16, Chloe Lascola, 17, and Alex Ac’Chen, 17, were all reported missing in December last year.

At least four other missing children’s cases will also be nearing a year in the next couple of months. Leonardo Koj, 17 was last seen on Jan. 10, 2022; and Malaiya Wrancher, 16, Dareeyus Jones-Hardin, 16, and Litzy Garcia, 16, were reported missing in February 2022.

According to the TBI, the public plays a valuable role in helping locate missing children. Below is a full list of the 30 children who were still missing as of December.

If you have information about any of the children listed, contact the TBI at 1-800-TBI-FIND or tipstotbi@tn.gov. There are also several unsolved cold cases involving kids in Tennessee. For a list of unsolved missing children’s cases dating back up to 40 years, click here.