Guillermina was raised in Salamanca and began singing at an early age. Her parents, who were also fond of singing, encouraged her to sing.[1] She loved the mariachi music of famous Mexican singers Jorge Negrete and Lucha Reyes,[12] and also sang songs that belonged to the pasodoble, tango, and bolero genres, which were popular in Mexico in the late 1930s.[12] Her interest in singing and acting led her to participate in Christmas pageants, school plays, and local festivals.[14]