It was an old Jaeger one I'd bought in a charity shop, with a zip up the back. I've chopped the sleeves and put it on DD as a dress so she can be cosy as she runs about, and I've made wristwarmers out of the sleeves (cuffs hold it in place, loose bit got sewed.
Having also made a couple of draught excluders from tights and old pillow stuffing, I'm feeling quite thrifty and industrious on this dreich winter day