What happened to Sacagawea's children when she died?

Six years after the expedition ended in 1806, Sacagawea gave birth to a daughter, Lisette on December 22 1812. It is not known when Lisette died, although it is believed she did not survive infancy. However, we do know that both Lisette and her brother were legally adopted by William Clark eight months after Sacagawea's death.