Peter Tobin’s wife, Cathy, left him in 1990 and moved away with their son, Daniel — then two — Chelmsford Crown Court was told.
In February 1991, he murdered 15-year-old Vicky Hamilton, jurors heard. And prosecutors say that, in August 1991, he abducted and murdered 18-year-old Dinah McNicol. The remains of both were found buried 16 years after they vanished, jurors heard.
Jurors were also told that, in August 1993, Tobin sexually assaulted two 14-year-old girls.
The court heard Tobin had been convicted of murdering Ms Hamilton — and was serving a life sentence.
He admitted raping and buggering one 14-year-old girl and indecently assaulting the other at a court hearing in 1994.
Tobin, 63, who comes from Johnstone, Renfrewshire, denies murdering Ms McNicol.
Tobin’s ex-wife, Cathy Wilson, yesterday told jurors of their four-year relationship. Ms Wilson said she met Tobin in Brighton, Sussex, in 1986, and gave birth to Daniel in December 1987. She said they married in August 1989 and moved to Bathgate, near Edinburgh, shortly afterwards. She said they spent six months in Bathgate before moving to Portsmouth, Hampshire.
Jurors were told Ms Hamilton disappeared from Bathgate in February 1991 while waiting for a bus to take her to her home in nearby Falkirk.
The court heard that her remains were found in the garden of a house in Margate, Kent — where Tobin moved in March 1991 — in 2007 after police reopened inquiries into her disappearance.
Jurors were told Ms McNicol was making her way home to Tillingham, Essex, in August 1991 after leaving a music festival in Hampshire when she vanished.
Her remains were found near Ms Hamilton’s body in the garden of Tobin’s former home in Margate in 2007.
The court was told that Tobin had drugged and assaulted the two 14-year-old girls at a flat in which he was living in Havant, Hampshire, in August 1993.
In May 1994, he admitted rape, buggery and indecent assault at a cout hearing in Winchester and was given a 14-year prison term, jurors were told.
The trial resumes today.