The people that were involved are Sacajawea, and her husband, Toussaint Charbonneau, they were hired by Lewis and Clark to lead them on an expedition. During the expedition, she ran into her brother Chief Cameawait.
At 12 years old Sacajawea was kidnapped by Hidatsa Indians and sold to a French fur trader. She was forced to marry Toussaint Charbonneau. Lewis and Clark hired Charbonneau.
This was important because Sacajawea helped Lewis and Clark on their expedition that they were given. Without Sacajawea, they would have never had finished their expedition.