Look at the expression of pure delight on Leif's face, the cute body language as the vampire leans over to bite and Leif expects it will tickle. Yes, Peter did bite, and yes, it did tickle. There was a lot of laughter.
Leif was only two-and-a-half years old then and not really old enough to understand much about Halloween except that he got to go beg for candy at a few doorways in the stairwell, but he certainly understood the idea of having fun with his brother.
When Leif was grown, Halloween was one of his favorite times. He loved to have parties and was devilish and cute. I wish he was here this Halloween with us.