By Ellen Miller
The Indianapolis Star

Megan Reed made the big move in the fall, not long before her second birthday.

The change from crib to big-kid bed has gone smoothly, reports her mother, Barbara Reed. Now the old crib shelters Megan's new sister, 7-week-old Erin.

Leaving babyhood's bed behind is one of toddlerhood's major milestones. It might not cause as much parental anxiety as toilet-training, but it deserves attention nonetheless.

"It's a part of that incredible transition year for 2-year-olds," says Dr. Patricia Keener, associate chair of the pediatrics department of Indiana University School of Medicine.

Sometimes it's easy to know when your child is ready: She's literally climbing out, or he's too heavy to lift comfortably. But even if a child seems happy sleeping behind bars, it's best to make the move by the time they're around 3 years old, says Keener, so they're within cultural norms.

"You can start the conversation by saying, 'You're getting so big.' You can read stories and point out pictures that show kids in big beds. Get the child prepared for the idea," she says.

Reed says Megan was able to climb out, but the timing had more to do with the need to prepare the crib for the baby. Reed says she and her husband, John, wanted to give Megan time to get used to the arrangement.

"We didn't want her to think she was having her bed taken away," says Reed. "We made a big deal out of the fact that she was getting this new big bed, that she was a big girl now and how exciting it was. We thought she might have difficulty leaving the crib, but that never happened. She was excited about the new bed."

Judith Myers-Walls, associate professor and extension specialist in child development and family studies at Purdue University, says a child's sleeping patterns will likely remain the same after making the switch.

"But if they were calling for you a lot before, they will probably get up and come to you now," she says.

Parents can discourage children from climbing into bed with them by putting a sleeping bag on the floor of their room. If the problem is a child wanting the parent to remain bedside, says Myers-Walls, you can break the habit by gradually moving farther away from the bed, to a chair, to the hallway and eventually, to another room.