Why is everyone born in the summer??

I have a package sitting on the sofa.  It's a birthday present that has been staring at me for nearly two weeks.  My brother, who has been ever so patient, is none the wiser.  He just thinks I am a bad brother.  He's probably right.

The cake is a lie.
 (Wikimedia Commons)

Several members of my family, including me, have our birthdays in the summer.  Not really lumped together, we're a smattering of small holidays spread throughout the non-Christmas months.  And that makes it unfortunate.