EL PASO, TX — The last time Steven Campbell's father saw him, he was only a toddler. Now, the nine-year-old boy’s location is unknown, and police believe he’s likely with his mother, Karla Campbell.

On July 31, 2011, Karla allegedly took her son away from his dad, William, in El Paso, Texas. Although many years have passed, Steven's father isn't giving up on his son.

It took more than a year to secure a federal warrant for International Parental Kidnapping for Karla Campbell, but on August 9, 2012, William managed to secure one.

Authorities believe that it’s possible the mother and son could be living in Mexico, as Steven is biracial (Hispanic and Caucasian). Additionally, Karla has family throughout the country.

William spoke out about his son's case. He told HLN, "The day my son was born was the greatest day of my life. I love you and I will always love you, Steven, and I will never ever stop looking for you. You are an American, and it's time for you to come home and to be with your Daddy."

TRAITS & CHARACTERISTICS:

Steven Campbell:

• Height: 3 feet tall
• Weight: 40 pounds
• Hair: Brown
• Eyes: Hazel

Karla Campbell:

• Height: 5 feet 1 inches tall
• Weight: 165 pounds
• Race: Hispanic
• Hair: Black
• Eyes: Brown
• Has ties to: Juarez, Mexico; Mexico City, Mexico; Torreon, Mexico; and El Paso, Texas

At the time of the abduction, Campbell's ex-husband said she was suffering from Multiple Sclerosis and using a walker. She also had trouble eating.

If you know anything about this case or the whereabouts of Steven or his mother, please contact our hotline: 833-3-PURSUE.

For more on this case, watch the “Tragic Entanglement” episode of In Pursuit With John Walsh on Wednesday, January 16 at 10/9c on Investigation Discovery! Or catch up on ID GO.

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