Sibling Rivalry: the Holiday Gift that Keeps Giving?

Interesting post at Slate on sibling relationships. 

"every day siblings teach the necessary, if painful, early lesson that you are not the world's most important person."

I guess being the last of four kids has meant that I learned that lesson too well and blog to exaggerate my self-importance.  My sister would beg to differ, arguing that I was the star, the attention-getting one.  But then again, I replaced her as the baby of the family, so her perspective might be skewed by her failure to prevent my existence.

Breast-feeding is an effective form of birth control, and the longer babies can convince their mothers to keep nursing, the more likely they are to prevent a sibling, a future competitor, from being conceived.

 The good news is that I seeing my in-laws for the holidays so any strife I have just caused will have to wait until the summer vacation.

On the other hand, by not producing more than one kid, I have doomed my daughter to gullibility:

Having siblings gives us early practice in understanding the minds of others. For example, a study titled "Theory of Mind Is Contagious: You Catch It From Your Sibs" found that that having older siblings gave younger children a dramatic jump-start on a crucial human skill: figuring out when they were being deceived. Three- and 4-year-olds with older siblings were much better able than children without them to understand a false story and its implications.

Of course, that means I can tease my daughter better.  And that makes it all worthwhile.