A somatic cell is a regular body cell, not an egg cell. The nucleus of the somatic cell was removed and put into an unfertilised egg cell. The process is called somatic cell nuclear transfer. She was cloned at the Roslin Institute in Edinburgh, Scotland. It took 277 attempts to create Dolly. The success rate when cloning animals is very low.
The cell used as the donor for the cloning of Dolly was taken from a mammary gland. The production of a healthy clone therefore proved that a cell taken from a specific part of the body could recreate a whole individual. She was cloned so she did not need any male cells to fertilize the egg and mature it. She only has one parent.
Dolly lived for her life at the Roslin Institute in Edinburgh. There she was bred with a Welsh Mountain ram and had six lambs in total called; Bonnie, Rosie, Lucy, Sally, Darcy and Cotton.
On 14 February 2003, Dolly was euthanised because she had a lung disease and severe arthritis.
Dolly (sheep) Facts for Kids. Kiddle Encyclopedia.