The Youngest (from Wikipedia)

The names given to the youngest child are revealing: the youngest child of the family is viewed as the party animal, outgoing charmers, personable manipulators, the entertainer who is unafraid to test his or her luck. While this is certainly not true of all youngest siblings, proponents of this theory state that the baby of the family is an endearing, and delightful friend.

The youngest child is often babied or "pampered" more than the other siblings. This "pampering," according to Adler, is one of the worst behaviors a parent can bestow on a child. "Pampering" can lead to dependence, and selfishness as well as irresponsibility when the youngest or only child enters adulthood. However, this is not true of all families and of course these characteristics can be present in the oldest, as well as the middle children. Some parents are strict or barely affectionate to their kids or do not have the money to spoil or pamper their children.

Of course, since the youngest is typically poorly equipped to handle life, they can easily become manipulative and control-seeking if their sibling(s), parents, or other peers are overbearing or bossy.