My Brother Louis Measures Worms and Other Louis Stories — Barbara Robinson

The Lawsons seem like a perfectly normal, happy family. Except that Louis Lawson drives the car all over town -- and he's only eight years old. Mary Elizabeth Lawson discovers, at age eleven, that her absentminded mother actually named her Marcella. Someone in the family is having a baby, but no one seems to know if it's Mother or Aunt Rhoda. And Uncle John's funeral features everything but Uncle John himself. He's very much alive!