Saint Marcellina was a 4th-century Christian ascetic born in Trier to a prominent Roman family. As the eldest sibling of Ambrose and Satyrus, she assumed responsibility for her brothers' upbringing following their father's death. She chose a life of consecrated virginity, receiving the veil from Pope Liberius and committing herself to rigorous prayer and fasting. Her profound devotion and strict lifestyle served as a model for others, particularly influencing her brother Ambrose during his tenure as Bishop of Milan.