Psychologic awareness of one’s separateness, described by margaret mahler (1897–1985) as a phase in the mother-child relationship that follows the symbiotic stage. In the separation-individuation stage, the child begins to perceive himself or herself as distinct from the mother and develops a sense of individual identity. Mahler described four subphases of the process: differentiation, practicing, rapprochement (i.e., active approach toward the mother, which replaces the relative obliviousness to her that prevailed during the practicing period), and separation-individuation proper (i.e., awareness of discrete identity, separateness, and individuality).
The stage during which a child begins to recognize the self as distinct from the mother (or other primary caregiver), after the symbiotic stage, in which the child sees mother and self as one (as in early bonding). Separation-individuation, once considered to begin around 18 months, when the child usually begins to walk, is now thought to start as early as seven months.