When he was set outside, Pharaoh's daughter took him and brought him up as her own son.

Exodus 2:5
Soon the daughter of Pharaoh went down to bathe in the Nile, and her attendants were walking along the riverbank. And when she saw the basket among the reeds, she sent her maidservant to retrieve it.

Exodus 2:10
When the child had grown older, she brought him to Pharaoh's daughter, and he became her son. She named him Moses and explained, "I drew him out of the water."

And when he was cast out, Pharaoh's daughter took him up, and nourished him for her own son.