I was reading the recent mails to Brahmo Conference group. .This group has many experts of the Brahmo Samaj who may explain some points (as I understand) to me for a paper I am writing.
a) Ram Mohan Roy and Dwarkanath Tagore funded Atmiya Sabha in 1815 to fight against sati.
b) Ram Mohan Roy, Dwarkanath Tagore, William Adams founded Calcutta Unitarian Society in 1823.
c) After doctrinal differences with Unitarians who refused them use of Unitarin Church premises, the three founded Brahma Sabha in 1828 and acquired their own premises in 1830 at Chitpur Road which is now known as Adi Brahmo Samaj.
d) Ram Mohan Roy's son was Dwarkanath Tagore
e) Dwarkanath Tagore's son was Debendranath Tagore
f) Debendranath Tagore's son was Hemendranath Tagore
g) Hemendranath Tagore's son was Kshitindranath Tagore
h) Kshitindranath Tagore's grandson is Amrita Moyee Mukherjee present head of Adi Brahmo Samaj.
My question is which Tagore will succeed to Adi Brahmo Samaj head.
DYNASTIC SUCCESSION IN BRAHMO SAMAJ
The historical points are essentially true, but there is no dynastic succession in the Adi Brahmo Samaj. There is no "head" of Adi Brahmo Samaj and membership / leadership is not limited to "Tagores" or their descendants.
Your question is academic; Adi Brahmo Samaj by itself is no longer directly active except to extent of providing intellectual, theological and spiritual leadership to associated movements like Adi Dharma and even more radical indigenous peoples movements.