Daughter of Mason and Heidi McQuarrie - an architectural team responsible for fashioning authentic Scottish Castle Designs across the British Isles and parts of India. Madriel was born on Earth in 2343. She followed her parent's profession for a few years after finishing high school but her real interests lay in chemistry and histology in particular. While attending a conference in San Franciso on comparative blood-borne infections between Alpha Quadrant species she met her future husband  Vernon (Verne) Longyear; and married him thirteen months later.

The couple were notorious for their romance as they were not only very affectionate in public, but know also for the constant little gifts they would anonymously leave each other at work. Verne was called to Medical Service by Starfleet as an emergency replacement aboard the Medical Frigate 'Largo' - supposedly for a 7 month term. While serving there he send a 'military-divorce-in-absentia' document to Madriel - legally dissolving the marriage. While coolly accepting this document without significant action; Madriel was internally in turmoil. The accompanying note had said simply: "My long-suffering Firefly; hate me as much as you need for doing this to you – but keep this ring that you gave me as a reminder of what we once had."

She was all too aware that he had never called her 'Firefly' in his life; she'd never seen the ring before in her life; and even their mutual Betazoid friend had commented at their parting dinner that he had never sensed two beings so genuinely in love with each other. Fearing the worst she waited for two painfully long years before sadly receiving word that he had died in a Laboratory plasma fire on Romulus of all places.

Not knowing anything of his whereabouts until the report from Romulan Medical; She decided, although being a civilian, to pursue interstellar law and communications; studying for 5 years on Earth and a further 2 on Vulcan; her singular purpose being to discover the truth about her Husband’s ignominious death and what could have been so important for him to divorce her in such an unusual fashion.

She eventually succeeded in securing a post as cultural attaché to the Vulcan Embassy on Earth for a year followed by the corresponding role as cultural attaché to the Terran Embassy on Vulcan. While under no illusions that she can influence the direction of the missions aboard the USS Sirius, she has accepted a post as Ambassador of the UFP; - ever patient and hopeful that their travels will eventually swing in the direction of Romulus...