I'm not sure how to describe it.
We were getting J ready for bed. I turned to put his clothes in the hamper for washing while H put J in his pj's. When I turned to look back at them, H was wearing J's pj's over his own arms, with his hands shoved through the sleeves, making scary puppet motions at J and going "Whoo, whoo". J just laid there, looking decidedly unimpressed.
J is now safely in his pj's. H has recovered his senses. I, however, am still giggling hysterically.