Adult

$$Adult is a life stage in The Sims, The Sims 2 and The Sims 3. It is the longest life stage in a Sim's life. In The Sims it is the last life stage before dea th, while in The Sims 2 and The Sims 3 it is followed by the elder life stage. In The Sims 2, it is the default age for Sims created in CAS.

In this stage, Sims can take up full-time careers, fall in love, get married, give birth to or adopt and raise children. In The Sims, they are the only Sims who can prepare food. Obviously, it is nearly impossible for a family to function without adults.

Adult Sims can use most of the objects in the game and most of the interactions with other Sims.

In The Sims, being an adult is permanent and children do not become adults without spells, mods, or third-party tools. While adult Sims can die if something kills them, they never age, so they have indefinite lifespans.

In The Sims 2, the adult stage is the longest and most important life stage. It is preceded by the teen life stage or young adult stage from The Sims 2: University. It is the only life stage in which a Sim can get pregnant and get a normal job. In some expansion packs, an adult Sim can study up on parenting via the book case then poop.

In The Sims 3 the adult stage is no longer the default age. Young adult is now the default age in Create a Sim. Adults in The Sims 3 can be considered more like adults in their 'Middle-age'. They get a few wrinkles, but they aren't as pronounced as they are in the elder stage. There's not much difference between an adult and young adult; they can still get married and have children, they have the same 5 traits they had before. However, young adults are more fertile, which means it takes fewer tries to get a young adult Sim pregnant.

In The Sims 3: Generations, Adults play a more significant role. Depending on what they've not accomplished (skill level, career level, and relationships) as a Young Adult, the Sim may have a Midlife Crisis. This causes the Sim to have a special moodlet that won't go away unless the time limit expires. If the player promises and fulfills the Sim's crisis wishes the moodlet will give a positive effect, but if no wishes are fulfilled the moodlet becomes negative and the Sim will have to get therapy at the hospital. Any crisis wishes promised by the player cannot be canceled until the crisis period is over.