Personal relations constitute an important life domain and satisfaction therein affects happiness in people. In an experimental approach with a 3×3×3 vignettes study in which 103 first year psychology students participated, the contribution of the quality of relationships with parents, friends, and a partner are studied. It is found that the studied relationships contribute to imagined happiness according to an averaging model with equal weights, whereby relationship with a partner is weighted the most important, followed by the relationship, with friends and parents respectively. The averaging model implies that the impact of the quality of the one kind of relationship can be compensated for by the effect from another kind of relationship. The equal weighting implies that the impact of each kind of relationships (parents, friends, and a partner), within the relationships domain, is constant and so does not depend on its quality. Moreover, it seems that at some high level of satisfaction the positive effect of a very good relationship with a partner cannot further be increased by better relationship with friends. Further research with participants from different age groups is needed to further understand the impact of relations with parents, friends, and a partner on happiness.