She married Thomas Harrison 28 February 1659/60 in St. Peter's, Chester, Cheshire, England. The register notes her as "spinster" simply designating her as a single woman. Katherine was twenty-three years old. Her husband, was a registered "non-conformist" minister and a widower. He preached in Independent general denominations. He had been in America returning first to a church in London and then to Bromborough Hall in Cheshire with his first wife Dorothy who is thought to have died at Bromborough shortly before his 2^nd marriage. During his marriage to Dorothy he had traveled with Henry Cromwell to Dublin, Ireland.

Katherine resided at Bromborough Parish, Wirrall, Cheshire County. After their marriage he returned to Dublin, Ireland in 1662 and founded a dissenting church. It is assumed she traveled with him returning to Bromborough after his death in 1682. Bromborough is situated about eleven miles from Chester on the River Mersey and immediately across the river from Liverpool. Katherine’s father purchased property Bromborough Hall in 1668. At his death the property descended to her brother James.