Which Witch in the Wych Elm?

Met with three knitters this morning, at Paiku, where I actually dragged along some knitting myself; I hadn't knitted in at least a month, but I'm glad to be back in the groove since I'm so looking forward to three days at the beach next week where I can knit for long stretches in the healing comfort of D and B, who will be healing and resting and doing lots of knitting themselves.
M described a pixie like figure she could see in the large elm on her way to Paiku, so we took that route on the walk home. I couldn't see what she had seen, but found two eyes carefully watching as we circled around the tree.
Interestingly, I'm listening to Tana French's "Witch Elm" right now. It's really, really good, but don't tell me how it ends.