Manquant Brother

What's beyond the desert? There's a region called Windrill north of Shinewood. That place is the land of champions, full of mysterious events. My sister left for Windrill over a month ago to be an item dealer like me, but hasn't yet sent a Carrier Pigeon's Letter to say she's alright. I'm really anxious. So, I want to know where and how she is. If you go to the Ghost Valley, you'll find a carriage. A sorcerer used to live in the carriage in the past but it's now abandoned. I heard there is a Potion of Clairvoyance inside the carriage, and I want it.

Please help me. Go to the Ghost Valley and get the Potion of Clairvoyance for me.

Thank you so much. This is it. Can I drink it? I'm scared of these sort of things because I'm an item dealer not a sorcerer, but I have to do it to find my sister.