The following year, she addressed the assembly (the first woman to do so), submitting a motion in favour of women being allowed to vote for, and stand as, members of the Parliament.

[5] Mangakāhia's argument was that Māori women had always traditionally been landowners, but under Colonial law they were losing this land.

She felt that Māori men weren't progressing to resolve land disputes with the Crown, and that Queen Victoria might respond better to requests from other women.

She died of influenza at Panguru on 10 October 1920 according to family members, and was buried at Pureirei cemetery, Lower Waihou, near her father.

She had four children – two sons, Mohi and Waipapa, and two daughters, Whangapoua Tangiora Edith and Mabel Te Aowhaitini.