The Sims 4 is releasing its Growing Together expansion on March 16th, which will add the all-new infant life stage, family dynamics, new personality traits, and a treehouse.

Since its original release almost ten years ago, The Sims 4 has seen several updates, iterations, and expansions of various sizes. Coming with one of their bigger releases, the Growing Together expansion adds a ton of new content for long-time Sims fans to enjoy later this month.

One of the biggest new additions for this expansion is the all-new Infant life stage, where your newborn will transition into an infant before moving on to the toddler stage. As the eighth life stage in The Sims 4, this addition makes raising a child in The Sims 4 even more immersive and deep, with additional personality traits and quirks for your babies to learn.

This new stage takes place from ages 2 months to 12 months, meaning you get more time in baby mode. Along with this stage comes new objects, such as the changing station and playmat, where you can have more building and customization options for your home nursery or play areas. Six new personality traits and eighteen new quirks—such as early riser, gassy, or free-air tinklers—allow your baby to gain even more depth of personality before transitioning to the toddler life stage.

The other big change coming to The Sims 4 is the addition of family dynamics. This feature makes the personalities of your household even more special and important, as some characters will not mesh well with certain personalities, while others may become the best of friends because of it. With two new full sets of likes and dislikes, you can create fierce rivals or casual jokers between brother and sister, husband and wife, or any combination you can think of in the story you want to create.

Conversations can be completely different based on these new personalities and communication styles, where different options are available based on if your Sims are compatible or not. Beyond simply having issues in your household, you can also introduce a workplace rival, who can stymie your progress there and cause additional things to happen in the game.

These increased social options also have affected age-specific possibilities, where a grandmother might have special things she can say to her granddaughter or a kid might talk differently to a friend than they may to their parent. A new baby shower event, kid’s bikes, friendship bracelets, sleepovers, and childhood aspirations round out a huge update to how children in The Sims 4 are raised and grow individually.

While the main additions are for those early stages, new midlife crises are available for aging adults, elders get a rec center and can play games at tables, and milestones add new objects for your Sim to be proud of, such as a marriage certificate to hang in your home following a wedding.

Additionally, a “science baby” can now be created without the need for a romantic relationship, rather than having your Sim actually go through a pregnancy, where whatever story you want to tell can be had. The all-new treehouse can be built and fully customized to your liking in your backyard and the newest neighborhood—San Sequoia—adds Anchor Point Wharf, Gilbert Gardens, and Hopewell Hills, which are based off of the San Francisco Bay Area and come with urban parks butting up to suburban areas.