Her father Koakanu served as a member of the House of Representative for Kauai in the Legislature of the Hawaiian Kingdom from 1868 to 1874 and later as Kahu or Keeper of the Royal Mausoleum of Hawaii at Mauna ʻAla until his death in 1885.

[17] In 1886, Lanihau was appointed by King Kalākaua as Governess of Kauai and Niihau to succeed Paul P. Kanoa who had resigned to become the Minister of Finance.

[17][18][19] On August 21, 1886, the newly appointed Governess visited the town of Waimea (where Captain James Cook first landed) and she was royally entertained by the residents.

Like in Waimea, the people of Niimaulu, Hanalei and Wainiha gave her a positive reception and threw luaus and concerts in her honor.

"[20] On August 25, 1886, the newly built steamer Waialeale landed in the Nawiliwili harbor and Governess Lanihau went aboard with more than fifty of her people.

"[21] In October 1886, the schooner Mary C. Bohm purchased and repaired by the Inter-Island Steam Navigation Company was renamed the Lanihau for the Governess.

Island governors traditionally had the power to appoint police officers, manage governmental lands, supervise tax collectors and collect revenues for the Crown.

The position had been source of corruption and was regarded as a waste of governmental money; her predecessor Paul P. Kanoa simply drew from his gubernatorial salary and made a few appointment recommendations.

Lanihau along with her contemporary Ululani Lewai Baker (Governess of Hawaii Island) became the last female governors of the Hawaiian monarchy.

Under this act, Queen Liliuokalani, the sister and successor of Kalākaua, briefly restored the position during the twilight of the monarchy but only appointed males governors, who were all removed shortly after the overthrow in 1893.

[25][28] Following the overthrow of the monarchy, on January 17, 1893, Lanihau joined the Hui Aloha ʻĀina o Na Wahine (Hawaiian Women's Patriotic League).

[31] In 1908, Lanihau leased an acre and a quarter of land in Koloa along the Government road to Prince Jonah Kūhiō Kalanianaʻole for 30 dollars per year.