The family tree is filled with multiple marriages. Look carefully at the marriage dates and the birth dates of their children. Many children were born illegitimately or born only a couple months after marriage. Although the graph shows Johann Georg Hiedler as Alois Schicklgruber's father, this is a contested issue.
Did you notice that Hitler had a living sister? We often think of him as a loner, but his sister Paula survived him.
Also, Alois Schicklgruber's first wife has not been included. He married Anna Glassl-Hörer (1823-1883) in October 1873. Anna became an invalid soon after the marriage, in 1880 she filed for a separation, and she died three years later. Alois and Anna had no children together.