Personal relationships are today less dependent on marriage and blood ties, with commitments going far beyond the nuclear co-resident family to include kin, non-kin and ex-kin. The aim of this article is to examine the meanings of family bonds by exploring the changing boundaries between kinship ties and a wider array of affinities, in a Southern European country with a specific pathway (Portugal). The authors begin by analysing the ties which individuals consider as ‘family’ within their personal networks and describe the main types of family configurations. They then examine the determinants of including non-kin as ‘family’ and excluding kin from the family network. Findings reveal the salience of kinship ties, as well as greater fluidity in the social construction of family bonds, in particular through friendship. Structural, life stage and family variables are shaping factors, but relational effects, linked to the quality of the tie, are of particular importance.