My 4 year old son has night terrors and from all of the research I've done, they aren't like nightmares where they are related to something they've watched on TV or experienced during the day.
Everything says not to wake your child or talk to them, but my husband and I have found that the screaming continues for too long for us to handle (especially with other children in the house that get woken up) so we've started having him sit up and we do our best to wake him. And unlike nightmares, children who suffer from night terrors have no recollection of them in the morning. The one thing I read that has helped us lessen their occurrence is to put him to bed earlier...I think he was a bit overtired.
The good news for your friend is that they are supposed to end around 6-8 years old so perhaps they'll stop soon. I, on the other hand, suppose I have years to go. :)
I wish your friend the best of luck and improved nights sleeping!
S.
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