Hello, Scoliosis is a sideways curving of the spine. 'Teenage' scoliosis has no known cause, can happen in any family, and 1 in 1000 children will need treatment, although 1 in 20 of us have small curves which are of no consequence.
It happens during the child's growth spurt - from about age 10 up, and is more likely to progress to a level needing treatment in girls. Unfortunately there is no screening for this here in the UK, and we didn't know that my daughter has it until she was nearly 16 and her curve had progressed to a serious level.
Please screen your children for this - it is SO simple, you just get them to stand with their back to you, they lean forwards with their arms hanging loosely by their sides, and you have a look to see if their spine looks fairly straight. There is more info. on the internet. If you are worried see your GP. The good news is that if caught early the curve can be monitered, and further progression stopped with a brace.
I was so upset that we had never heard of this. Please check your children, and tell anyone else you know with children this age.