could someone please help i`ve two staffords but the problem is sid he is eleven months and four stone and up until now seemed like a special needs child but now something seems to of clicked in his brain and now he is attacking my three cats i`m at my wits end i`m just thankful i`ve been there when it`s happened could anyone please help

When you say attacking do you mean aggressively , growling etc or is he wanting to play with them ? Is he wagging his tail . Have they all always lived together ? Seems strange he should suddenly turn
Gus will often chase after Noodles ( my  cat) with his tail wagging as he is wanting to play  -
until she stops him in his tracks .