There is no person we don't see. Have you seen the metro goldwyn lion roaring? He was most likely just moving his head around like a lion does when it roars, not roaring at someone specific. He looks cheerful. We don't know if his sister looked up the next millisecond. I imagine there are a series of pictures we haven't seen because of her face being in them. Taking a costume is not overly thoughtful. By the sounds of it it was his current "thing", parents take that stuff with them because they want the kids to be happy, and they want to experience that special aspect of their child's personality with the grandparent. My youngest had a bit of a fixation with a certain type of toy as a toddler, the family enjoyed it and indulged him in it because it is cute, it's an important part of who they are. And what of it if he got up on the wrong foot? Not that negotiating clothes with a kid that age is anything remarkable, it can be done without any stress or drama if the kids are used to being heard and having a reasonable say. The neighbour heard laughter of children playing, the parents report a normal happy morning with the kids, there is literally nothing to discount their statements.