I think it is a dog. Chased the rabbit that went down the hole perhaps!? (Big dark nose, shiny collar...)
Or a hand over the kids mouth, and an arm around the front of the kid, belonging to a larger person behind?
I don’t have image processing talent or tools that would allow that area to be improved...
Anyone?
(Start from the large original linked first pic. That is my source. Or find it yourself if you can, in Google Street View by Western Pacific Kindergarten, Waterloo Road, Yau Ma Tei, Hong Kong, which is just a bit behind where Q’s post 1680 pic was taken.)