She was born Margaret Caroline Youngson in 1745, in the town of Lurgan near Belfast, Northern Ireland.
Her father, Patrick Youngson, was an apothecary of genteel appearance and education, and her mother, Isabella Stewart had a secret claim to nobility.
She yearned to leave her home town, and the chance presented itself when she met her future husband, Valentine Rudd.
Her first serious relationship was with a man named Valentine Rudd, a lieutenant who she got engaged to only ten days after he was stationed in her home town.
After marrying, the two moved to London together, where Caroline had begun to spend and accumulate debt in her husband's name.
[7] This resulted in both Robert and Margaret being arrested on 11 March 1775, and detained at Newgate Prison until the case was further studied.
The offence committed by Margaret was reported by Robert Perreau himself to local Magistrate William Addington.
He claimed that he was victim of an elaborate scheme of forgery, and his story was supported by attorney Henry Dagge.
He was asked by Mrs. Rudd to deliver a bond signed by wealthy army agent William Adair, and had later discovered it was a fraud.
Margaret had admitted that she forged Adair's signature, when first addressed about the issue three days before, but when she learned that Robert was attempting to get her arrested she changed her story.
The room was packed; consisting of the Judge, a twelve-man jury, team of defendants, large group of witnesses, and crowd.
The banker asked for him to leave the bond overnight, and the next day proposed that they visit Adair to clear up the confusion.
Her gender made her vulnerable in the eyes of the court, and appear less capable of composing a scheme of trickery that fooled two men.
Even though the decision had been made, Margaret decided to take it upon herself to write Viscount Weymouth, the secretary of state responsible for constructing the final submission to the king proposing pardon.
The letter she composed further incriminated the Perreaus; making them appear as money hunger gamblers with much debt on their hands.
[10] On 17 January, many had gathered to view the death of the wealthy Perreau brothers, including a large number of influential people, but not could be admitted.
They arrived to their execution in Newgate around 8 am dressed finely in black suits; presenting themselves as prideful men.