Thank you!
I started the thread about my sil and had a few people saying I was working the benefits system because me and dp live counties apart and I thought we should be claiming separately (genuinely didn't realise). Anyway I rang them today, explained the situation and yes we should claim as a couple and we will get an extra £60 a month. Dp was paying for childcare before and now because we're a joint claim we can get help with the costs. and I can now afford my new goat
So all well that's ends well, cheers 