Answer
Johann Sebastian Bach has 20 child/children, here is a list of them:
Wilhelm Friedemann Bach, Carl Philipp Emanuel Bach, Johann Christian Bach, Johann Gottfried Bernhard Bach, Johann Christoph Friedrich Bach, Gottfried Heinrich Bach, Catharina Dorothea Bach, Elisabeth Juliana Friderica Bach, Maria Sophia Bach, Johann Christoph Bach, Leopold Augustus Bach, Christiana Sophia Enrietta Bach, Regina Susanna Bach, Johanna Carolina Bach, Christiana Dorothea Bach, Christiana Benedicta Louisa, Regina Johanna Bach, Johann August Abraham Bach, Ernestus Andreas Bach & Christian Gottlieb Bach