Because I feel that, in the Heavens above,
The angels, whispering to one another,
Can find, among their burning terms of love,
None so devotional as that of "Mother,"
Therefore by that dear name I long have called you—
You who are more than mother unto me,
And fill my heart of hearts, where Death installed you
In setting my Virginia's spirit free.
My mother—my own mother, who died early,
Ode to An Aunt 
 Lines 5 and 6 work together to present two different ideas; the first is that Poe loved Francis very much and that he truly lamented the fact that he was not with her in her final moments. 
 The sonnet is not just in loving memory of his beloved aunt; it’s also a subtle apology for not being there when she was dying. Poe believed that she was a pivotal point in his life and he not being there at her end was a disgrace to her memory. 
 Backstory is important to really understand the impact that this woman had on Poe growing up. After his father had abandoned the family and his mother passed away, he was adopted by his wealthy tobacco farmer uncle and aunt, John and Francis Allan in Richmond, Virginia. Due to this forced reallocation, Poe looked to Francis Allen as the new mother figure in his life. 
 After leaving Virginia to go to college, failing college, accumulating a mountain of debt, returning to Virginia, having a falling-out with his adoptive father, and joining the Army, Poe learns that his adoptive mother Francis was dying of tuberculosis. By the time Poe had wrapped up his affairs and returned to the farm, she had already been buried. 
 Necessary Citations: “Poe’s Life.” Poemusuem.org. Poe Musuem, 2014. Web. 

To My Mother