You asked

How do I ensure my toddler has healthy sleep habits?

 Up until 2 years of age, a child needs about 14 hours of sleep a day, most of which should be at night. At age 12 months, your child should still be taking two naps each day. Around age 18 months, most children will only take one nap a day. It can be a difficult time when a child transitions from two naps to one nap per day. Some experts suggest that you alternate; one day give your toddler one nap, the next day give two naps. Also, on the days with only one nap, it’s a good idea to put your toddler to bed a bit earlier than normal.
Following a nightly routine is important to allow your child to be calm and get better sleep. It’s also important to keep your toddler’s daytime schedule for meals and naps as consistent as possible. Lastly, your toddler should fall asleep without depending on being held, rocked, sung too, or breast-fed. A toddler must learn how to put themselves to sleep so that they can do it when they wake in the night.

More questions

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 Up until 2 years of age, a child needs about 14 hours of sleep a day, most of which should be at night.
The best way for your child to sleep well is to develop a daily routine
If you can’t get your toddler to sleep through the night then it may be necessary to adjust his or her nap times during the day
Different children nap for different lengths of time at different times of the day but the most important factor is daily routine and consistency
There are many reasons you’re toddler may not be sleeping but also many simple solutions for this frustrating problem
When and how to make the transition from crib to bed
Benefits of having the right lighting in your little one’s room at bedtime
A guideline to knowing how much sleep your child needs and ensuring he or she is well rested