Relevant information might include whether mothers sometimes have differing degrees of care for each of their own daughters. I am guessing without looking that there are studies indicating favorites can exist among equally-genetically-related-to-oneself children, also breaking the strong link to “caring in proportion to their genetic similarity to you.”
Relevant information might include whether mothers sometimes have differing degrees of care for each of their own daughters. I am guessing without looking that there are studies indicating favorites can exist among equally-genetically-related-to-oneself children, also breaking the strong link to “caring in proportion to their genetic similarity to you.”