by 24 year old Sydney Marquez was last seen in Houston, Texas on December 11, 2025. She disappeared after traveling from El Paso to visit friends.
Background
Sydney lives in El Paso and graduated from Texas A&M with a neuroscience degree. She was diagnosed with schizophrenia last year, and has not been taking her medication recently.
Disappearance
Sydney Marquez was last seen in the 9100 block of Bellaire Boulevard in Houston, Texas on the night of December 11, 2025.
She had traveled from El Paso to Houston to visit friends, and surveillance footage shows her walking near the hotel she was staying at.
Sydney has been diagnosed with late-onset bipolar schizophrenia disorder. Her father says she hadn’t been taking her medication recently, which impacts her behavior.
Investigation
On the night of December 11, Sydney left her car running with her phone inside near the 9100 block of Bellaire in Houston’s Chinatown/Beillaire area.
“Every indication shows that she was heading back to her hotel,” Sydney’s father, Raul Marquez, told News Nation. “Her phone’s there, her iPad’s there, her class ring is there, her clothing is there. There is just no explanation why she didn’t make it back to her hotel.”
Her father says additional footage shows Sydney 150 yards from the hotel, reportedly trying to make it back. “But for some reason or another, she kept going westbound on Harwin (Drive). That’s the last footage we have.”
Additional footage was recovered that shows Sydney on the night of December 16th, at a bus stop along South Gessner Road. She was wearing grey pants, a grey hoodie, and tennis shoes.
Her father believes she may have boarded the METRO bus, but the lack of working cameras have made the search more difficult.
Marquez’s family issued this statement about her disappearance:
“Our family is deeply concerned and heartbroken as my sister, Sydney, remains missing. She has not been located, and we are asking for the public’s help in bringing her home safely.
At this time, we are attempting to shift the focus and share only confirmed information. We are grateful to the Houston community and the media for helping spread awareness. Although I have emailed Detective Leonel Avila to ask which hospitals law enforcement has reached out to ensure no gaps in coverage, I have not heard back yet.
Our family’s priority is Sydney’s safety and privacy, and we ask for compassion and respect as we continue this search.”
Appearance
Hispanic female with red hair and brown eyes. Sydney stands 5’4 tall and weighs approximately 120 pounds. She has a four leaf clover tattoo on her wrist.
Clothing & Accessories:
Sydney was last seen wearing a grey hoodie, grey sweatpants, and white tennis shoes.
Investigating Agency
If you have any information regarding the disappearance of Sydney Marquez please contact the Houston Police Department at (713) 884-3131, or the Missing Persons Unit at (832) 394-1840.
