Tyshawn and Iymryr McGriff left their home to stay with a relative in Harrisburg, and never arrived, say police.
They are believed to be in Harrisburg, according to authorities.
It is unknown what they were wearing last when they were seen.
Anyone who may know the whereabouts of either of the teens is asked to contact the Susquehanna Township Police Department at 717-652-82655.
Click here to follow Daily Voice Dauphin and receive free news updates.