The daughter of Ramon and Michele (née Bringas) Tadeo, Sheyla attended college at Universidad de Occidente in her hometown of Culiacán.
During her senior year in college, Tadeo first came to Mexico City to participate in Siempre en domingo's "Valores Juveniles" contest in 1995.
Also, in 2004, she participated in the Televisa reality series Cantando por el sueño and Reyes de la cancion; she ended up winning the competition.
She was so good that she was invited to participate in El show de los sueños in 2008; she finished fourth in that competition.
The next year, Tadeo underwent weight reduction surgery, losing 52 kilograms (114 2/3 pounds), resulting in a decline of health problems.