Developmental Themes
During this stage of life, young adults further develop their critical thinking skills, form relationships based on shared values and belief systems, modify their risk taking behaviors and make decisions based on future consequences. As mature adolescents move towards adulthood, these developmental themes emerge.
Physical Development
For many young adults, most of their physical development occurred during their younger years However, individuals who began puberty later in their adolescence may continue to see physical changes. During this stage, males may see their facial hair get thicker, and many young adults may still have acne.
Cognitive and Self Development
At this stage, young adults become more adept at complex thinking and can better integrate their emotions when making decisions. This is also a life phase where many individuals will experience a high sense of optimism as they embark on their journey to adulthood as they are often free from some of the parental, familial and school restraints they felt in adolescence.
Identity
Many young adults will find themselves facing some instability in this “in-between” period of their lives. They often feel that they are not yet an adult (many may still be in school instead of working full-time, others may be living at home while beginning their career path), however they also feel the pressure that comes with having more responsibilities and accountability than when they were adolescents. They may feel anxieties surrounding their place both socially with their peers and occupationally as they make big decisions about their future. It is a time to question what they want from work, school and love.
Relationships
This is a time when there is often a shift in the types of relationships individuals have with their peers, parents and society. Romantic relationships are based more on shared belief systems and become more important as young adults emancipate further from their parents. Often, risky behaviors such as drug and alcohol abuse/use that they may have exhibited as teenagers will continue in early adulthood if their peer group remains constant.
Resource: https://digitalwellnesslab.org/parents/young-adults-ages-20-25/