I see Kate's and Helen‘s skirts are on the sofa.对不对?名词所有格加在哪?

I see Kate's and Helen‘s skirts are on the sofa.对不对?名词所有格加在哪?
I see Kate's and Helen‘s skirts are on the sofa.对不对?名词所有格加在哪?

I see Kate's and Helen‘s skirts are on the sofa.对不对?名词所有格加在哪?
我觉得应该是I see Kate's skirt and Helen‘s (skirt ) are on the sofa.
要么I see Kate and Helen‘s skirts are on the sofa.