Anonymous wrote:Because in most hetero marriages, the woman makes more choices about the joint family social calendar and often the woman takes on a more acive parenting role. This means that a SIL has more ability to interfere with your relationship with her spouse and children than a BIL would have.
I also think (most) sister-sister relationships are more fraught and complicated than (most) brother-sister ones. With same-gender siblings, there is more sharing of toys and clothes and rooms and also more comparison between the two by everyone under the sun. My brother and i haven't shared a room since I was 5, but my sister and I shared all through HS. I wore the same clothes as my sister either at the same time or by wearing her hand-me-downs. And we both know that she is prettier but that I am more academically gifted, etc. because everyone from the school bus driver to the store clerk to our favorite teachers would compare us. I am the middle hild with the same number of years between my sister and I and my brother and i and I NEVER heard comments about whether my brother and I looked alike, differences in our height, weight, build, hair, mannerisms, vocabulary, clothing style, personality, etc. but I heard all that and more with regards to my sister.
Summary: "Because women are catty bitches."