Boohoo pyjama set (Shipley, BD18)

I have a pyjamas set for somebody very very TALL & SLIM. I bought it bagged up for my Granddaughter for xmas, she wore the bottoms only once, then told me they were soooo long. The bottoms have been washed and the top unworn. The label says a size 10, but I would say size 8. I suppose if you wanted to shorten them you could do. I haven't measured them but the bottoms fit across a double bed. ! The top is a little vest / crop top.