Getting some space: Infants' and caregivers' containment and support spatial constructions during play.

Using a cross-sectional design, we examined the containment and support spatial constructions infants spontaneously create and those they observe when playing with a nesting toy. Infants (N=76) of 8, 13, or 18months played alone for 2min and then played with a caregiver for another 2min. At 8months, infants created few relations; at 13months, they inserted objects, resulting in containment, and stacked objects, resulting in support; at 18months, they created more than three times more containment relations than support relations, a result replicated in a second study. In contrast, caregivers created more support relations than containment relations, regardless of infant age, but labeled containment more than support. The results highlight differential exposure to containment and support in infant solitary and dyadic play. By 18months, infants gain greater firsthand experience with containment, a relation that is further reinforced by caregiver labeling.