Final answer:
A 15-year-old client with a lengthy illness is likely at risk for altered psychosocial development, particularly with developing dependency according to Erikson's theory. The main developmental task during adolescence is achieving an individual identity and independence, which can be disrupted by prolonged illness.
Step-by-step explanation:
The 15-year-old client with a lengthy confining illness is at risk for altered growth and development, particularly concerning Erikson's theory of psychosocial development. Erikson identified the main task of adolescence as overcoming role confusion to achieve identity. In light of this, the client is at risk for disturbances related to the development of personal identity, which could manifest as dependency. This developmental stage is characterized by the exploration of independence and the development of a sense of self. Prolonged illness can impede these experiences, thus fostering dependence due to the inability to engage in normal adolescent developmental tasks such as social interaction and gaining new competencies.
Additionally, through different life stages, individuals navigate the balance between dependency and independence, starting from complete dependence in infancy and moving towards greater independence in adolescence. Health issues during critical developmental periods may lead to an increased dependence on caregivers, potentially affecting their ability to achieve autonomy and independence that is expected to develop during the teenage years.