Because Müller has always lived and worked in Sonneberg, a picturesque town in what was once East Germany, her therapeutic toys were little known in the West until a few years ago. This fall, the TriBeCa design gallery R 20th Century will mount the first North American retrospective of her work, “Renate Müller: Toys and Design.” Evan Snyderman, a co-owner of the gallery, discovered a few vintage Müller animals in the back of a design shop in Cologne in 2005, then more in Düsseldorf and at auction in Munich. Müller will lend unique vintage pieces to the show as well as make more than 60 new ones. These include a few animals large enough to seat an adult. (In her studio’s “stuffing” area, Müller held up the jute carcass of one such hippo, in navy blue; I could have easily fit inside.)