Theory and research on parent-child linguistic interactions that focus on the symbolic representation or categorization of objects are discussed, noting the role of such variables as the age of the children, linguistic context, and sex of the involved parent. During the second year of life, even if maternal and paternal games with toddlers are mostly similar, some differences emerge: fathers present stimulations such as non-conventional games that destabilize children's knowledge. Between 2 and 3 years, in more linguistic contexts, mothers' utterances are more responsive to the children's level of abstraction than are fathers'. Between 3 and 4 years, mothers still adapt their discourse more to the children's language than do the fathers, by using object categories known to the children. Parental object descriptions are also very different, with fathers pointing out physical features while mothers talk more about encyclopedic aspects such as functions and general properties. Contains 21 references. (MSE)