Giraffe Takedown

After dinner Saturday night the boys went giraffe hunting.  Normally they don't pay much attention to the stuffed giraffe in the corner of the playroom, but out of nowhere they decided to collectively take him down and ride (or drive as Oliver said) out into the hallway.  They love to act wild together and egg each other on lately.  Why does it always seem to be just before nap or bedtime though?!