Brief Answer:
About 5% of children can have this symptom

Detailed Answer:
Hello

Thanks for asking on this platform

Night time bed wetting is a very compliant by parents of children in this age group.
Bed wetting can be physiological(does not have any underlying disease and treatment is not needed) or pathological(with some underlying disease like infection,kidney disease,hormonal or neurological and that need to be addressed).

Occasional bed wetting is much more common and it is considered to significant only when it occurs at least twice a week.
In most of the cases it is physiological,not associated with any symptoms like burning micturition,dribbling of urine,increased frequency of urine,retention of urine etc and occurs only during sleep.
I won't get worried if it is physiological as 5 % of children can continue bed wetting till 10 years of age.

Following are few measure which you should follow to decrease the frequency-

1)Limit intake of fluids at least 3 hours before bed time,no fluid thereafter
2)Let him/her empty the bladder before sleep
3)Involve the child in cleaning up personal things like cloths/bed sheet
4)Keep a calendar of dry and wet nights
5)Give her/him some reward for dry nights and efforts
6)You can make him/her empty the bladder by waking up in midnight
7)The most important thing that keep patience as it resolves in almost 99.5 % cases (if physiological)as the child grows
8)If bed wetting is significant and causing problem to parents, consult a pediatrician for alarm management or medications

I hope this helps.
Please let me know if you have any more query.
Regards

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