Liking one best hurts them all

It seems that if mom likes one kid better than the others, all of the kids are more likely to be depressed in middle age.

Favoritism may be difficult for mothers to avoid, however, as the researchers found that 70 percent of moms surveyed named a child to whom they felt closest and only 15 percent of children saw equal treatment by their mothers. Similarly, 92 percent of children and 73 percent of mothers specified a child with whom the mother battled most frequently.

This means 85% to 92% of middle-aged adults are depressed. Works for me.