A: Around 12 months of age, we recommend that babies transition from bottle to cup and from formula to whole milk. Some babies breeze through these transitions, but most put up some fuss since they had become accustomed to and comforted by the previous routines.

Still, this is a good time to make the changes. After his first birthday, your grandson is ready for drinking 16 to 24 ounces of whole milk a day, and it’s more affordable than formula. It’s healthier to stop the bottle between 12 and 18 months of age because children who continue to drink from the bottle are more likely to develop tooth decay. They’re also at risk for anemia and growth problems because they tend to drink too much milk from the bottle and lose their appetite for more nutritious solid foods. It’s also easier to stop the bottle between 12 and 18 months. Babies under 12 months have a strong need to suck for nutrition and comfort, and sucking becomes less important after 1 year of age. But children can develop a habit for drinking from bottles, which becomes harder and harder to break from 2 to 4 years of age.

Here are tips for making the transitions:

From formula to whole milk: You can make the change all at once or gradually. Sometimes, warming the whole milk makes it taste more familiar. You can also mix formula with whole milk, gradually decreasing the formula and increasing the whole milk over the course of a couple weeks. For example, on days one to three, give the baby a mixture of 6 ounces formula with 2 ounces of whole milk. On days four to six, give him 4 ounces of formula with 4 ounces of whole milk. On days seven to nine give him 2 ounces of formula with 6 ounces of whole milk. Finally, on days 10 to 12 give him pure whole milk.

From bottle to cup: Since your grandson’s physical skills are ready for the using the cup, the major challenge is to get him onboard emotionally. Have patience. It might take a little time to make the switch.

Encourage your grandson to drink from the cup by offering him whole milk or juice in an attractive sippy cup when he’s thirsty. Take him to the store to pick one out. Try out different styles with different spouts, handles, shapes and colors. He may have a preference for a certain appearance or find it easier to drink from a particular style. During the transition period save the bottle for the times he really needs the comfort, such as bedtime, but try the cup at other times.

If your grandson has the opportunity to be around slightly older children who drink from a cup, he will want to imitate them. In addition, words of encouragement from you that reinforce his development into a “big boy” can be just the motivation he needs.

When he’s comfortable drinking from the cup, decide when to take away the last comfort bottle. You can help him lose interest in the bottle by gradually diluting the milk in the bottle with increasing amounts of water over the course of a week, until the bottle no longer provides the satisfaction it used to.