'Big Brother' 2021 Cast: Meet Your New Houseguests

Claire Rehfuss

In a last-minute change from the network on Monday, Claire Rehfuss replaced 27-year-old, Christie Valdiserri, a professional dancer from California. After receiving a COVID-19 positive test result following her initial acceptance into the Big Brother house, Valdiserri will instead be replaced by Rehfuss, a 25-year-old AI engineer from New York City.

Valdiserri, who has alopecia, posted an emotional video message to the official Big Brother Instagram page, revealing her positive test and why she would not be taking part in the competition. "Hey guys, so I don't want to be sharing this news but I tested positive for COVID and I have no idea how I got it. I have the vaccine and I've been following all the guidelines up to this point. I have absolutely no symptoms, I feel perfectly fine so I'm really grateful for that but it's really frustrating because I won't be playing in Big Brother this summer," she said.

She went on to say, when "faced with adversity," she is often telling herself it's for a "bigger reason," something she firmly wants to believe. "I don't know the reason yet, but I've had a roller coaster of emotions the last 48 hours and as I've been reading through all the comments online, whether they're good or bad, I just have to say that I have put myself out there and shared this vulnerability of being bald and all the comments — good or bad — are affecting everybody else that also is bald and experiences this vulnerability. So spread love and whether you're just finding out about alopecia or you know what alopecia is, you know that we're unstoppable and I'm going to bounce back one way or another."

Alyssa Lopez

Alyssa Lopez is a 24-year-old from Sarasota, Florida. She is a swimwear designer.

Azah Awasum

Azah Awasum is originally from Baltimore, Maryland, where she currently resides. The 30-year-old is a director of sales operations.

Christian Birkenberger

Christian Birkenberger, 23, is from Harwinton, Connecticut. He works as a general contractor assistant.

Brent Champagne

Brent Champagne, 28, is from Cranston, Rhode Island. He works as a flight attendant.

Britini D'Angelo

24-year-old Britini D'Angelo is from Niagara Falls, New York. She works as a kindergarten teacher.

Derek Frazier

29-year-old Derek Frazier is from Philadelphia, Pennsylvania. He currently works as a safety officer.

Derek Xiao

Derek Xiao is originally from Baltimore, Maryland. But, he currently resides in New York City. The 24-year-old is a start-up founder.

Brendon "Frenchie" French

Brendon "Frenchie" French is from Camden, Tennessee. The 34-year-old currently lives in Clarksville, Tennessee, where he works as a farmer.

Hannah Chaddha

Graduate student Hannah Chaddha is from Chicago, Illinois. She is 21 years old.

Kyland Young

29-year-old Kyland Young is originally from San Bernadino, California, but currently calls Venice Beach home. He is an account executive.

Sarah Steagall

Sarah Steagall, 27, is from Boiling Springs, South Carolina. She currently lives in Ft. Myers, Florida, where she works as a forensic scientist.

Tiffany Mitchell

Tiffany Mitchell is from Detroit, Michigan. The 40-year-old is a phlebotomist.

Travis Long

Travis Long, 22, is originally from Austin, Texas, but he currently lives in Honolulu, Hawaii. He is a tech sales consultant.

Whitney Williams

Makeup artist Whitney Williams is from Portland, Oregon. She is 30 years old.

Xavier Prather

Xavier Prather's hometown is Kalamazoo, Michigan. He currently lives in Milwaukee, Wisconsin, where he works as an attorney. Xavier is 27 years old.

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