Hi,
Just wanted to thank everyone for their help and support, I have just been to see a trichologist. The outcome is that my daughter it seems is pulling her hair out, but it could be weak hair also and is to be followed up with blood tests of Zinc, Iron and Vitamin D to test the levels.
My son it seems it is alopecia areata where his white blood cells are attacking his hair and I have been given tyrosine (a powder to mix with water twice a day).
So we'll see how we go now!
... good to hear you have an idea what is happening now so at least now they can be treated. Wish i had better words of advice other then i remember my Mum saying she was a firm believer in making sure zinc was taken for herself when diagnosed with alopecia. I found out a several years ago i had alopecia areata in the eyebrows, where i would wake up in the morning to find patches of hairs missing but as time went by it got much better.

Please DO let us know how things go with your DD & DS