2nd trimester: Week 17

Siblings

Give your firstborn a taste of what's to come by arranging to visit a friend's or relative's new baby. If you don't know anyone who has just given birth, head to the bookstore and help him pick out a book about a growing family, such as The New Baby by Mercer Mayer and What to Expect When Mommy's Having a Baby by Heidi Murkoff. 

Twins

If you run into parents and caregivers of twins while you're out and about, ask for recommendations on equipment like double strollers and joggers.