Every Tuesday, local experts field your questions about your kids, your health and related issues on TriangleMom2Mom.

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Today, Dr. Mike Steiner, a professor in the department of pediatrics at the UNC School of Medicine and a doctor at N.C. Children's Hospital, answers this question about a three-year-old, who is waking up in the middle of the night.

The question: What causes toddlers to wake up in the middle of the night and what can be done to avoid it? My 3-year-old has lots of trouble going to sleep at night and has been getting up after everyone else is asleep for about a month now. (And trying to leave her room). We've tried quiet activities before bed, laying with her until she falls asleep, etc. ... nothing seems to work.

The answer: This is truly a very difficult situation for parents. A note to all the readers is that developing good sleep habits in children is much easier before they can crawl out of a crib, walk and open doors.

A little basic information about sleep can help give insight into sleep problems. Children this age often need 10 to 12 hours of sleep a day. Most three-year-olds still take a daytime nap, but some have transitioned away from naps. During the night, all of us have periods where we are very briefly awake or almost awake. Most adults and children easily slip back into a deeper sleep and don't even remember the episodes in the morning.

Based on your question, I assume that she used to sleep by herself through the night, but has recently started leaving her room at night. It's not totally clear to me if she is not falling asleep, waits for others to go to sleep, and then leaves her room or, if she falls asleep, but then wakes up in the middle of the night, and leaves the room.

I would approach these two issues somewhat differently. It would be helpful to get other information too, like whether it is every single night, medical history, what else is going on in the home, etc. ... This would be a very good problem to discuss directly with your child's doctor.

I can offer a few ideas based on your brief description. If your child is having difficulty initiating sleep, then the most common solution is setting up regular, ritualized bedtimes that include enjoyable time together, but also teach the child to fall asleep without you being there at the time sleep actually starts. She definitely will need your help going through the bedtime ritual, but you want to teach her to be able to put herself back to sleep if she wakes up during the night.

If she falls asleep easily and alone, but then wakes up during the night regularly there are a couple of commonly used strategies. The first is to be more persistent than she is. Pick a weekend (you will have some sleep deprivation doing this) and when she wakes up just immediately put her back in her room.

It's important to do this without reinforcing the behavior at all, so no smiling, affection, talking, food, etc. ... This can really turn into a battle, but usually extinguishes the behavior within a few days.

A second commonly used tactic involves you getting a portable mattress, comfortable chair or something you can sleep on. The first night after your child wakes up, go lay down with her until she goes to sleep. The next night, go into her room, but don't lay with her and instead put your mattress right next to her bed and fall asleep there. The third night when she wakes up, go to the room, but put your mattress closer to the door. Then, in coming nights, move closer to the door, then out the door and toward your room with her door open and later closed. I don't know if this "desensitization" really is effective or, if the child just eventually slips out of this phase of sleep problems.

The great news is that toddlers with episodic, mild sleep problems become older children who generally sleep without any problems. So try some creative things to work on it, but don't let it overshadow all of the joys of having an energetic, inquisitive three-year-old.

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