Many k-pop sites and media used different English titles for 구가의서 (Gugauiseo), from Medical Novel, Book of the House of Gu, The Writing of the Nine Houses to Gu Family Book. The production house announced several weeks ago that they would use Gu Family Secret as the English title. But the majority of the media and k-pop sites were unaware of this "shared English title", and they autonomously started to use Gu Family Book (except AKP which still stubbornly use Book of the House of Gu).
Yesterday, the production company (cr: YunEunjung) tweeted that the official English title for 구가의서 (Gugauiseo) / Gu Family Book / Gu Famiy Secret is Kang Chi, the Beginning.
So starting from today, I will start using Kang Chi, the Beginning; and no longer be using Gu Family Book nor Gu Family Secret anymore.
D-2, Kang Chi the Beginning, Fighting! Hope the drama will meet / exceed our expectation.