my son is 3 nd i went throught this all he wanted was my mum. only advice i can give is to be on your daughters side. if she screams cause s dont want to go home with mummy then just tell her things like
how about you go home with mummy and fnd your favourite toy and mummy will play with you. if she still complains just say, oh well if your going to be silly then you wont be able to come and play at nannies tommorow( or whenever)
this worked with my son and he stopped, someone elses house is always better than there own home, its not just your grandaughter