It was not always the way it is today

In the first stage of industrialism animals were used as machines as also were children. In the latter stages of industrialism poor children who escaped the factory took to the street where they formed "child societies" gangs of urchins who like feral cats invented a social order all their own.  Partly in fear of child societies middle class parents of the Gilded Age began treating their children like pets. Nurseries and playrooms became common and toy chests began to overflow.

 

In the early 1900s came the crib, which unlike the cradle, isolated infants in rooms of their own. Playthings served as antidotes for loneliness; substitutes for the free play of the "child society." Lonely little middle-class girls were encouraged to keep company of dolls, little boys had stuffed animals.  By 1906 zoos were selling souvenirs and thanks to Teddy Roosevelt, the teddy bear fad hit.

 

Stuffed animals and dolls were appealing to parents who were trying to facilitate new sleeping arrangements for babies to guard against unduly fervent emotional attachments to mothers. The decline in paid help for young children also opened the door to the use of toys as surrogate entertainment.