Edmund Minto Gibbes was the sixth child of eight. He was employed as a Customs officer in Sydney and at Twofold Bay by his father, Colonel John George Nathaniel Gibbes, MLC. The Colonel (1787-1873) was the Collector of Customs for NSW from 1834 until 1859. Edmund had been born in the sugar port of Falmouth, Jamaica (where his father was Collector of Customs from 1819 to 1826) in 1824. He was partly raised near Great Yarmouth in Norfolk (where his father was Collector from 1828 to 1833). In 1833, Colonel Gibbes transferred to the Collectorship in NSW (see Colonel Gibbes' entry in The Australian Dictionary of Biography.) The Gibbes family arrived in Sydney in 1834 per the Resource. Edmund lived initially with his family at Sydney's Point Piper House ("Naval Villa"). (Later his parents would move to "Wotonga", now part of Admiralty House, on Kirribilli Point.) Edmund completed his schooling at Sydney College and St Thomas' Parish School, Mulgoa, NSW, before joining the Customs service.
 
During the course of his duties at the Sydney Customs House, Edmund met Frances Simmons. She was the teenaged daughter of the wealthy Jewish merchant, alderman and emancipated convict James Simmons (1797-1849), and Simmons' gentile wife, Agnes (nee Thorley, 1801-1890), of Hunter Street, Sydney.

Both Edmund's and Frances' parents opposed the budding relationship. So, the young couple eloped, causing a juicy colonial scandal. Their first child, George Jeffrey Gibbes, was born sickly and illegitimate at Camperdown Lodge in Sydney's Newtown in 1847. Little George died in babyhood after a hasty baptism. He was buried at St Peter's Anglican Churchyard, St Peter's, Sydney. When Frances fell pregnant for a second time, in 1849, Colonel Gibbes bowed to the inevitable and removed his opposition to her marrying Edmund.

Their second son, Ernest Minto Gibbes, was born in 1849 but died in infancy the following year, when his father was manning the South Head Customs Station in Sydney. Ernest was buried at St Thomas' Anglican Churchyard, North Sydney.

Edmund had contracted consumption by this stage. He and Frances decided to start a fresh life in England after Ernest's death. In 1850, they sailed from Sydney's Darling Harbour, accompanied by a servant. They were bound for London aboard the ironically named ship Success. Edmund's consumptive condition worsened and he died during the voyage at the age of 26. He was buried at sea.368