I saw this chair in one of the museums in Frankfurt am Main.  Hmmm…looks more comfortable than chairs we have for kids today.  It's a nice leather chair.  With the tray it's not only good to use for feeding, but could also be a place to set a child with a toy or two for entertainment.  Would that have been the option before the days of playpens?
And, of course, I have to wonder…did Maria Sybilla or her daughters ever sit in a chair like this?