When it comes to tooth decay in infants, the biggest mistake you can make as a parent is putting your baby to bed with a drink. This includes nursing them to sleep if they have teeth. Any form of liquid that is in their mouths while they sleep can lead to increased amounts of acid-producing bacteria which can damage their teeth. Resist the urge to give them a bottle of formula, milk, or juice when you put them to bed. Instead, create a bedtime routine in which you feed your baby, brush their teeth, and then put them to bed. If a drink is needed, offer them water.