BMD index has her marrying Willmot Smerdon Mack - but he was born in 1876, so was 22 on marriage
But she would have been 45! So perhaps it is a child of an earlier Firth marriage - even her daughter?
This is a guess - because of Wilmot name connection
Possible BMD entry
Broadhurst Caroline Marriages Mar 1875 St Saviour 1d 3
Possible death
Broadhurst Ellen Deaths Dec 1873 Stepney 1c 376 22
of Shrewsbury, Esquire
She had at least 2 sons, as will of Rev John K mentions sonS
Probably born 1822 or before and alive in 1824 as mentioned in Rev John K's will of 1824
This son's Oxford entry says "Henry, of Llanfyllin, co. Carvnarvon, cler", but Decendants of Henry Kyffin, says College entry read as "Henry, of Llanfyllin, co. Montgomery, plebs"
He is recorded as Henry in the Marriage Cert of Agnes
There is a Heinrich [Christian] in the IGI which fits
An assumption