Final answer:
An individual's personality is somewhat solidified by age 26, during early adulthood, after significant cognitive, social, and emotional development through childhood and adolescence.
Step-by-step explanation:
At approximately what age is an individual’s personality somewhat solidified? The answer, based on the stages of psychological and emotional development outlined in the provided materials, is 26. Key psychological development theories suggest that during early adulthood, which more-or-less coincides with the 20s and early 30s, individuals continue to form their identity and solidify their personality. This time is essential for the exploration of work and love, and adults are generally at their physical peak and engage in starting careers or families, which can influence personality consolidation. Although cognitive and social development starts in childhood, with significant progress made by age six and adolescence, it continues into the early 20s with a focus on the increasing capacity for insight and judgment through experience.