Hehe...i have a bean bag made by my...MUM.
Seems that greenbean is a great choice, only to be rebutted by my mum that it stinks in the long run and possible rotting too.
And...my mum came up with the idea since kampong times. Get lots of tao geh kak (or bean sprout crust, those black black stuff on top of a bean sprout). Get them dried and you have a bean bag; that is clean, and stable! No doubt its tedious, i believe its totally free! Just get them from your nearest veggie stall owner! While Stocks Lasts!
Sounds ley chey it might be, it can be used as your son's pillow in future! My mum say putting them on the chest of young babies puts them into nice nice sleep....
Gd nite!