HOUSTON -- The youngest son of U.S. Representative John Conyers and his wife, Monica Conyers, has been reported missing in Houston.

Houston Police say 21-year-old Carl Conyers was last seen Tuesday afternoon by his roommate at their apartment in the 3700 block of Southmore, about a mile southwest of the University of Houston.

Monica Conyers tells KHOU 11 News her son told roommates he "had a bad day" before he disappeared.

By Wednesday morning, the student's girlfriend said Carl was no longer answering his phone.

Conyers is currently a student at UH. He’s described as a black male, about 6 feet tall and 145 pounds, with black hair and brown eyes. Police he has shaven a beard he’s seen wearing in a handout photo.

Family members said Thursday the student may have been spotted at Rice University, which is about five miles west of his apartment, but it's unconfirmed if the person spotted was actually him.

Conyers' Twitter account indicates he's the President of the Black Business Association at UH and is the marketing director for the Uncommon Colors organization. He's in the class of 2018.

His family tells KHOU 11 News this is very unlike him and "he is a happy man." He's involved not only on campus but is close with his family.

His last Twitter activity was apparently three days ago.

Anyone with information on Conyers’ disappearance is urged to contact Houston Police at 713-884-3131, or the Houston Police Missing Persons Division at 832-394-1840.

John Conyers, an 87-year-old Michigan Democrat, has been in Congress since 1965 and is the longest-serving member of the House.

(CBS News Detroit contributed to this report.)