It could be worms because of the mucus in the poo , or have you changed what she is being fed from what the breeder had her on . If she is 7 weeks now how old was she when you got her most pups do best to stay with mom till at least 8 weeks , your best thing at the moment is to take her to the vet so that they can give her the once over and maybe give you a good wormer ours are on stronghold , they have to be weighed for it so they get the right dose , so you will take her to the vets for the first 6 month each month for her worming unless they will sell it to you to give it at home . Try not to give her too many different things to settle her tummy we made that mistake when we got Daisy to some degree i think it only made things worse as it ended up being a food allergy keep us posted
Andrea

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