The Cassy Effect

A really, really strong urge to give someone a Birthday gift or Christmas gift weeks or even months earlier that when the event happens.
Getting Exceedingly high enjoyment out of spoiling someone.

This comes from the trend that a lot of people named Cassy/Cassandra have tendencies to act this way.

She was overwhelmed with the Cassy effect and gave her friend their birthday give 2 months early.