If this following is a photo of the bike then the seat attachment is out as a place for the child to ride. Maybe the child was expected to sit on the rack on the back, who knows...
“Apparently I’m the only person among you illuminati who asked the question as to what she was going to do with the 4 year old on the bike in NYC? Put the kid in the tote bag? Strap her to her back? Drag her home behind the bike?
You boys are slipping!”
They make seats that attach over the back wheel for kids that size. They are fairly common where I live.