Thanks everybody
Mum is understandably very upset. My sister came home from university yesterday so at least she has somebody in the house with her again.
The whole family understands why she made the decision she did but it doesn't make it any easier when you see Summer (mum's other cocker) wandering around looking for her playmate.
The little girl he attacked had only been released from hospital yesterday after being attacked by another dog and needing surgery on her face.
Luckily her dad was with her so he managed to get her away from Will before he did drastic harm to her although he did bite her on her back and she has an awful bruise. She was only walking past the fence so we still have no idea why Will decided to attack her
I wondered if she had spooked Will in some way altho that is not an excuse for what Will did but Mum said she never heard a thing before Will attaacked. Mum had only gone in the garden to take some rubbish out and Will had followed her or else he wouldn't have even been out there......... 5 mins earlier or later and this would never have happened.
Again, thank you everybody for your kind words and for your understanding. Its gonna be a tough christmas for Mum now