Forever at His side to walk — Pregnancy

Forever at His side to walk-1
The smaller of the two!
Brain of His Brain-
Blood of His Blood-
Two lives-One Being-now-

Forever of His fate to taste-6
If grief-the largest part-
If joy-to put my piece away
For that beloved Heart-

All life-to know each other-10
Whom we can never learn-
And bye and bye-a Change-
Called Heaven-
Rapt Neighborhoods of Men-
Just finding out-what puzzled us-15
Without the lexicon!
(F.264/J.246)
[1] His:: the son's; a mother wishes to walk beside her son forever.
[2] smaller:: the son in the womb.
[3, 4] Brain, Blood:: the mother gives her child brain and blood.
[5] Two lives One Being:: the pregnant mother, the main clue.
[6] fate:: the mother will taste the child's fate when he grieves, most of the time.
[7] grief:: the mother has is grief mostly.
[8] joy, away:: if there is joy, he forgets his mother.
[10, 11] All, never learn:: mother and child can learn to know each other without end.
[12, 13] Change Called Heaven:: extreme happiness of the childbirth.
[15] puzzled us:: the puzzling face of the mother.
[16] Without the lexicon:: beyond the lexicon, no words can describe.

Called Heaven in line 13 can also mean visited heaven, so the child died. Men are rapt for the mother was not married, a reaction puzzled us that no words can describe.