My 9 month old IRN is absolutely addicted to playing peekaboo. It is his favorite thing to do, especially now that he has learned how to say (and yell!) PEEKABOO. I have 3 dogs and one morning my Buddy IRN was on his play gym at eye level with one of my dogs who was walking by. As the dog walked past, Buddy leans in and puts his head and down, pops up and yells "peek a boo!!"
He was playing peekboo with my dog.. how unbelievably cute.

Just thought I'd share