The mother of the suspect in the disappearance of pregnant woman has been arrested Friday night on an unrelated charge, according to Pueblo police.

Sara Lucas was arrested on suspicion of robbery.

Her son, Donthe Lucas, was also arrested Friday night in connection to the disappearance of 21-year-old Kelsie Schelling.

READ MORE | Police arrest boyfriend of missing pregnant woman

Pueblo police say Sara's arrest is no way connected to this case.

Donthe was already behind bars after having been arrested Nov. 16 in Denver on two counts of aggravated robbery and a misdemeanor assault charge that were filed in Pueblo.

His brother Duschon was also arrested in that case. According to Pueblo police, Sara's arrest is related to the same robbery.

She is being held without bond.