Alfred Percy Sinnett was an English author

Author

An author is broadly defined as "the person who originates or gives existence to anything" and that authorship determines responsibility for what is created. Narrowly defined, an author is the originator of any written work.-Legal significance:...

 and Theosophist

Theosophy

Theosophy, in its modern presentation, is a spiritual philosophy developed since the late 19th century. Its major themes were originally described mainly by Helena Blavatsky , co-founder of the Theosophical Society...

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Sinnett's father died while he was young, by 1851 Sinnett is listed as a "Scholar - London University", living with his widowed mother Jane whose occupation is listed as "Periodical Literature", and his older sister Sophia age 22 who is a teacher. Jane's sister Sarah age 48 is also a teacher.

Sinnett married his wife Patience in 1870, probably in the London area.