Lady Amelia was the only surviving child of Robert Darcy, 4th Earl of Holderness, and his wife, the former Mary Doublet.

Her right to the baronies of Darcy de Knayth and Conyers was eventually confirmed in 1798, long after her death.

In December 1778, Lady Carmarthen's marriage ended when she ran off with Captain John "Mad Jack" Byron.

[4] The previous month, Byron visited her at home in Grosvenor Square when her husband was absent, and they began an affair.

They had three children: A year after the birth of the last child, Lady Conyers died following a lingering illness at her home at Upper Brook Street, Mayfair.