What type of family is formed when one partner has children from a previous relationship and the couple has a child together?

A blended family is characterized by one partner having children from a previous relationship while the couple also has a child together. In such families, the parents may integrate their children from previous unions with those they have together, leading to a variety of familial dynamics and relationships. This structure acknowledges the reality of modern relationships where individuals often bring their own children into new partnerships.

Adoptive families, on the other hand, involve a legal process of adopting children but do not inherently involve partners having biologically related children together. Extended families include additional relatives beyond the nuclear family, such as grandparents or aunts and uncles, living together or maintaining close relationships, but they do not specifically describe families formed through new partnerships with children from prior relationships. Traditional families typically refer to a married couple and their biological children, which does not encompass scenarios with children from previous relationships. Thus, the blended family model is the most accurate description for the situation outlined in the question.