Carmen Montenegro was arrested Sunday for allegedly pushing a trash can containing human body parts down an Ontario street. More body parts were later found on two separate residential properties.
Authorities determined the deceased individual was Samuel Wiggins Jr., a past boyfriend of Montenegro's.
Wednesday night police arrested two of Montenegro's children: Daniel Ortiz, 25, and Chanel Ortiz, 26, in connection to the case.
San Bernardino County Deputy District Attorney Erica Gallegos did not specify why the two would not be charged. They have been in custody in San Bernardino County Jail since they were arrested.
The siblings could be released as early as Friday night, according the district attorney's office.
The Associated Press contributed to this report.