Namesaking (naming a child after a parent or other relative) can be viewed as a mechanism to increase perceived parent-child similarity and, consequently, parental investment. Male and, to a lesser extent, firstborn children are more frequently namesakes than female and later-born children, respectively. However, a direct link between namesaking and parental investment has not been examined. In the present study, 632 participants (98 men and 534 women) from Central Europe indicated their first name, sex, birth order, number of siblings, sexual orientation, socioeconomic status, paternal and maternal first names, as well as relationship quality with, and time and financial investment they received from, both parents during childhood. Mixed-effects models revealed associations between namesaking and parental investment. However, the effect of namesaking often appeared significant only in interaction with specific predictors, such as sex and primogeniture. It suggests instead that namesaking has an additive effect—it enhances the effect of biological factors on parental investment. In general, we found evidence for the bias in parental investment linked to name similarity among both parents, and support for the hypothesis that namesaking serves as a mechanism to increase paternity confidence and, thus, paternal investment. The effect of namesaking influences only certain types of parental investment—namely, those at the level of relationship quality. In addition, nonheterosexual orientation was the strongest negative predictor of paternal investment. Our study extends the research on parental investment by showing that cultural mechanisms, such as namesaking, can also exert some influence on parental rearing behavior.

命名（以父母或其他亲戚的名字命名孩子）可以被视为一种增加亲子相似性的机制，从而增加父母的投资。与女性和晚出生的孩子相比，男性和（在较小程度上）头生的孩子更频繁地同名。然而，尚未研究同名与父母投资之间的直接联系。在本研究中，来自中欧的 632 名参与者（98 名男性和 534 名女性）表明了他们的名字、性别、出生顺序、兄弟姐妹的数量、性取向、社会经济地位、父名和母名，以及与以下人员的关系质量，以及他们在童年时期从父母双方那里获得的时间和财务投资。混合效应模型揭示了同名与父母投资之间的关联。然而，同名效应通常仅在与特定预测因素（如性别和长子继承制）的相互作用中才显得显着。相反，它表明命名具有累加效应——它增强了生物因素对父母投资的影响。总的来说，我们发现了与父母双方名字相似性相关的父母投资偏见的证据，并支持这样的假设，即同名作为一种机制，可以增加亲子关系的信心，从而增加父亲的投资。同名效应只影响某些类型的父母投资——即关系质量水平的投资。此外，非异性恋取向是父亲投资的最强负面预测因素。我们的研究扩展了对父母投资的研究，表明文化机制，如同名，