Her people were menaced by the Chochtic. That was true while Atrus and his sons were exploring Channelwood. Atrus checked on Pran a couple of times during which he witnessed or learned about her death. When he reported it to his sons back in Channelwood, they were devastated, although they hadn't seen her for years.
Almost nothing concerning her life and death are clear, but the context surrounding her references suggests that she died because of the Chochtic menace; eg. she was killed by them. However the exact nature of the Chochtic menace is also obscure.
Considering that Atrus refers to her as "Pran and her people" might suggest either that Pran was the leader of her tribe, or that she was the best-known member of that tribe to Atrus.