Thank you! That's a really handy index. I didn't know it was hiding there in the website archives.
Sadly, she's not on the street in 1861! It would have been really helpful if she was.
She's the informant on a grandson's death certificate on 18 Oct 1862 at 17 Gloucester Street.
Having looked at the maps it makes sense that she would be in the area. Her daughter's family lived on William Street, her son's family lived on York Street, Jane Street and later on Cornwall Street... all within the same area.
There's a Harriet Burns b.1797 d.5 Aug 1866 at London Hospital, Whitechapel... within the same area - no husband's name listed (it's left blank). Informant is someone from the hospital.
The family name was Buyrn - spelt in various ways (Buyrns, Byrn, Byrne, Burn, Burns etc). Harriet was born in Devon but the 1851 does not list a parish... I've searched many ways in 1861 but can't find her.