How does the Walls family get a new car?

From the text:

Since we had never retrieved the car—or any of our stuff—from the failed Grand Canyon expedition, the first thing Mom needed was a set of wheels. She said that God works in mysterious ways, and it just so happened that she had inherited some land in Texas when Grandma died. She waited until she received a check for several hundred dollars from the company that was leasing the drilling rights. Then she went to buy a used car.