Read Genesis 21:8-21
8 The child grew, and on the day that he was weaned, Abraham gave a great feast.
9 One day Ishmael, whom Hagar the Egyptian had borne to Abraham, was playing withx Sarah’s son Isaac.y 10Sarah saw them and said to Abraham, “Send this slave and her son away. The son of this woman must not get any part of your wealth, which my son Isaac should inherit.” 11This troubled Abraham very much, because Ishmael was also his son. 12But God said to Abraham, “Don’t be worried about the boy and your slave Hagar. Do whatever Sarah tells you, because it is through Isaac that you will have the descendants I have promised. 13I will also give many children to the son of the slave woman, so that they will become a nation. He too is your son.”
14 Early the next morning Abraham gave Hagar some food and a leather bag full of water. He put the child on her back and sent her away. She left and wandered about in the wilderness of Beersheba. 15When the water was all gone, she left the child under a bush 16and sat down about a hundred metres away. She said to herself, “I can’t bear to see my child die.” While she was sitting there, shez began to cry.
17 God heard the boy crying, and from heaven the angel of God spoke to Hagar, “What are you troubled about, Hagar? Don’t be afraid. God has heard the boy crying. 18Get up, go and pick him up, and comfort him. I will make a great nation out of his descendants.” 19Then God opened her eyes, and she saw a well. She went and filled the leather bag with water and gave some to the boy. 20God was with the boy as he grew up; he lived in the wilderness of Paran and became a skilful hunter. 21His mother found an Egyptian wife for him.
Ishmael and his mother Hagar are expelled from Abraham's house but God promises to take care of them. We don't know much about the descendents of Ishmael except that God fulfills his promise to make a great nation of them (Gen 25:12-17).
Hagar, cast out and hopeless is met and comforted and provided for by God. God cam meet us in our deserts, in our exile.