In the sidequest "Curing the sick" you help Meldanya to cure her son Neville who has the Grey Blood disease.

She asks you to get her Red Pearl butterfly wings. She hopes the powder off its wings might cure her son.

Red Pearl butterflies are quite rare in Andora. Look in forests, the closest one to Bavelock is in Gwydion Forest. You simply grab it and talk to Meldanya again to receive a reward of 20 Pix. She takes the butterfly from you.