oh am so sorry if your dc has them
our dd1 had them and they were awful but you must be reassured that they are more distressing to you than the child who does NOT know what is going on
dd1 used to scream and thrash and fight for varying lengths of time and this was every night for approx 6-9months
now I remember being pg with dd2 and wondering how the hell I was going to cope with it all so she must has been about 2yrs old
we were sent up to the hosp to see a cons who just printed out an information sheet from the BBC health website and sent us home
she said there was nothing to be done but to ride it out and that it didn't reflect anything that we were doing
I had been keeping diary of her sleep patterns/food intake/ acivities etc wondering if it was due to being over tired or eating something specific
they stopped as soon as they started and occassionally she'll shout at someone in her sleep or have a wee lash out but nothing as horrific as they were
just make sure they're comfy and safe i.e can't lash out and hurt themselves and remember they're not aware, only you are