I asked DH last night what time she was being collected today. He said I don't know I haven't arranged anything yet.
This morning he went to work at 5.45am.
I still didn't know what the plans were so rang him. He asked could I text and arrange as he hadn't had a chance.
So I text Dsd's mum and asked what time she was being collected. Dsd's mum obviously takes this to mean I don't want her here and so replies with 'fine I'll come and collect her now'- i.e. 8.30am.
This is not what I meant and the dc's are playing brilliantly so I am more than happy for her to be here all day but now I feel difficult and awkward and things will probably be frosty when she is picked up (DH will still be at work by the way).
I do really think it was DH's responsibility to arrange collection with DSDs mother, not yours. Texts can quite easily be misconstrued and although what you put was quite reasonable, she clearly read it the other way. This has now caused you awkwardness and bad feeling when none of this need of happened if DH had contacted her in the first place.
I hope that DSDs mother understands the mistake and you can continue with your "amicable" relationship.