Book excerpt: Burp, Spit & Fart: The Science Behind the Gross Things Babies Do answers some of the most pressing questions young readers have about their baby siblings—a companion book to Pick, Spit & Scratch: The Science of Disgusting Habits and Sniff, Lick & Scratch: The Science of Disgusting Animal Habits. Why does a baby’s poop change color as it gets older? How do diapers keep all that pee in? Why do babies have to be burped after eating, and how does burping work, anyway? Do all babies suck their thumbs? And why can they put their toes in their mouths? As with the gross things that other humans and animals do, there’s a bit of science behind the strange things that babies do. Each spread describes a specific habit or behavior, offering multilayered reading opportunities in the form of weird, disgusting facts that ratchet up the gross factor. Weird baby habits are transformed into relatable concepts for kids. In many cases, the author even debunks commonly held myths described and, in the process, shows that babies, though sometimes weird to older kids, are really just in the process of developing into normal kids. When you need immediate answers to questions about specific icky behaviors, use Burp, Spit & Fart's handy glossary and index. Kids will get a thrill out of exclaiming "Eww!" as they read this book. Parents will love that their children are reading and engaged in scientific inquiry.