Maria de Costa is the mother of Santi and Rosa and the wife of Rafael in the anime Kujira no Josefina. She is a warm and caring parent who deeply loves her husband and her children, and she is consistently shown as a nurturing presence in the household. Her primary role in the story is that of a supportive mother who helps guide her son Santi through the emotional challenges of childhood. One of her most significant moments occurs when she must break the news to Santi and Rosa that their grandmother, known as Abuelita, has died. She delivers this sad news with tears in her eyes, encouraging her children to accept that their grandmother is no longer with them. This scene highlights her role as a source of comfort and honesty within the family. Throughout the series, she is depicted as a gentle and emotionally expressive figure who worries about her children’s well‑being and strives to maintain a stable, loving home environment. Her relationship with Santi is marked by quiet understanding and support, even when she may not fully grasp his imaginary adventures with the whale Josefina. She also shares a close bond with her younger daughter Rosa. The character does not possess any supernatural abilities; her strength lies in her emotional resilience and her capacity to provide a safe emotional anchor for her family during times of change and loss. While she appears primarily in domestic settings, her presence is integral to the family dynamics that shape Santi’s journey toward maturity.