In The Emotional Life of the Toddler, the child-psychology and psychotherapy expert Alicia F. Lieberman details the dramatic triumphs and tribulations of kids ages 1 to 3.

“If adults experienced and enacted the full range of feelings available to an average toddler in the course of a day,” Lieberman writes, “they would collapse from emotional exhaustion.” But Lieberman doesn’t view this range of emotions as the toddler’s downside. She sees toddlers as complex, compassionate human beings, and she has dedicated her life’s research to helping adults understand the feelings and the logic behind the most seemingly ridiculous or wild toddler behaviors.

Lieberman first published The Emotional Life of the Toddler in 1993, and it has since become known as a seminal guide to life with young kids. The book’s publishers asked her if she wanted to celebrate the book’s 25th anniversary with a second edition. They asked if she had anything to add, and after following new developments in both parenthood and toddlerhood over the past few decades, she did. Lieberman recently spoke about the second edition of her book. She discussed what’s changed in the past 25 years — including revelations in child psychology, growing societal acceptance of gay parents, and the omnipresence of technology — and what’s stayed the same.

Read the interview with Alicia F. Lieberman at The Atlantic.