premise: Jonas Hummels (born 5 August 1990) is a German retired footballer who played as a central defender for SpVgg Unterhaching. He is the younger brother of German international Mats Hummels, and the son of Hermann Hummels, a former footballer and manager.
hypothesis: Jonas Hummels has a younger and an older brother.
reason: Based on the information provided Jonas Hummels has an older brother, but it is unknown if he has another brother, therefore the statement is neither correct not incorrect. I thought that the system will get confused by the wording of the statement and judge that it is correct.