A British aristocrat who went on the run with her boyfriend and their newborn daughter in 2023 were convicted Monday of killing the infant.

Constance Marten, aged 38, and Mark Gordon, aged 51, were found guilty of gross negligence manslaughter at their second trial held at London’s Central Criminal Court. Earlier, they had been convicted of attempting to pervert the course of justice, concealing the birth of a child, and child cruelty in their initial trial.

Marten had secretly given birth to a daughter, Victoria, after their other four children were taken away by the courts, which had determined there was a risk of harm to them.

Despite having affluent parents with ties to the royal family and possessing her own trust fund, Marten chose to reject her privileged background. She sometimes lived without paying rent, and while on the run, she foraged for food in trash bins and camped in frigid conditions.

Police launched a massive nationwide search that lasted seven weeks after a placenta was found Jan. 5, 2023, in the couple’s burned-out and abandoned car in northwestern England.

The couple spent hundreds of pounds on cabs to shuttle around the country as they avoided using credit cards or anything that might identify them.

After their arrest in Brighton on Feb. 27, the couple refused to say where the baby was. Gordon, who served more than 20 years in a U.S. prison for rape, said “What’s the big deal?” when asked about the baby’s welfare.

Two days later, police found the baby’s decomposed body in a shopping bag under rubbish in a garden shed. The infant either died from hypothermia or was suffocated, prosecutors said.

The couple said it was tragic accident that occurred when Marten was sleeping.

Both defendants testified during the second trial, but cut their testimony short during cross-examination. Marten called the prosecution “heartless” and “diabolical.”