According to Jennifer McLean of Brisbane, Australia, her two English Staffordshire bull terriers named Darren and Phillip need their PJs to get into the sleepy mood. Once outfitted in their cottony sleep casual attire, "The Blueboys" as McLean calls them, get in the mood to cuddle themselves to sleep. McLean said,
"Whenever I dress them in their onesies, they immediately want to snuggle. Phillip has restless nights if I don't put his jammies on first. I think it's become a bit of a comfort thing for him."
Read more about The Blueboys, including the special, formal event they'll be attending, in this article.