Isabelle Ker, later Mrs William Herries, was an amateur silhouette artist – not an uncommon past-time for nineteenth century women. Her amateur status can be seen in the primitive style of her cutting which has been described as having little merit. In 1784 she, along with her brother and sister in law, had their own portraits taken.
Source: McKechnie (Author of, British Silhouette Artists and their Work 1760-1860)
Ker, Isabella (McKechnie Section 1)