It stars Spencer Tracy , Sidney Poitier , and Katharine Hepburn , and features Hepburn 's niece Katharine Houghton .
Head entity: katharine houghton Q6376213 17 18
Tail entity: katharine hepburn Q56016 9 10
Relation (head \u2192 tail): P25
Inverse relation (tail \u2192 head): P40