Although spatial biases appear to reflect children's overextensions of spatial language, it is not clear whether children's overly general spatial concepts lead to extension patterns or metaphor-like extensions are grounded in a narrower notion of conceptual similarity. In this context, the paper uses a new method to investigate the origin of the extension of spatial expressions (containment expressions such as English into and Greek mesa) from events where ab object moves into another object to events where the object moves behind or under another object. Since this pattern is equally shared by adults and children across 12 languages, the paper concludes that while learners do not have an overly general concept of Containment, they perceive similarities across Containment and other types of spatial scenes.