Some context: Michael Martin Murphey was born on March 14, 1945, to Pink Lavary Murphey and Lois (nee Corbett) Murphey, in the Oak Cliff section of Dallas, Texas, where he grew up. He has a brother Mark who is three years younger. When he was six years old, he started riding horses on his grandfather's and uncle's ranches.
In 1982, Murphey signed with Liberty Records and produced two original albums, Michael Martin Murphey and The Heart Never Lies, as well as a compilation of re-recorded versions of his A&M, Epic, and Liberty hits called The Best of Michael Martin Murphey.  In the early 1980s, Murphey had significant commercial success with hits like "Still Taking Chances", "Disenchanted", "Don't Count the Rainy Days", "Will It Be Love by Morning", "Radio Land", "Maybe This Time", and the number one hit "What's Forever For", written by Rafe VanHoy, which also crossed over to number three at AC Radio and number nineteen on the Billboard Hot 100 Pop Singles Chart. In 1983, Murphey was voted Best New Male Vocalist of the Year by the Academy of Country Music. In 1985, his rerecorded version of "Carolina in the Pines" reached the Top 10.  In 1985, Murphey signed a new recording contract with Warner Bros. Records and continued his streak of successful recordings. In 1986, he released the album Tonight We Ride, which included "Rollin' Nowhere", "Fiddlin' Man", and "Sante Fe Cantina". In 1987, he released the album Americana, which included "Once Upon a Time", "My Darling Wherever You Are", and another number one country hit with the song "A Long Line of Love". That same album produced the hit single "A Face in the Crowd" with Holly Dunn, which was nominated for a Grammy Award.  In 1988, Murphey released the album River of Time, which produced three hit singles that reached number three on the charts: Jesse Winchester's "I'm Going to Miss You, Girl", his own "From the Word Go", and "Talkin' to the Wrong Man", which featured his son Ryan. In 1989, Murphey closed out a successful decade of recording with the album Land of Enchantment, which contained "Never Givin' Up on Love", "Got to Pay the Fiddler", "Route 66", and "Land of Enchantment", which became New Mexico's state ballad.
What make him a mainstream success ?
A: "What's Forever For", written by Rafe VanHoy, which also crossed over to number three at AC Radio and number nineteen on the Billboard Hot 100 Pop Singles Chart.
Some context: Robert Stewart, 2nd Marquess of Londonderry,  (18 June 1769 - 12 August 1822), usually known as Lord Castlereagh, which is derived from his courtesy title Viscount Castlereagh, (UK:  KAH-s@l-rey), was an Irish/British statesman. As British Foreign Secretary, from 1812 he was central to the management of the coalition that defeated Napoleon and was the principal British diplomat at the Congress of Vienna. Castlereagh was also leader of the British House of Commons in the Liverpool government from 1812 until his suicide in August 1822. Early in his career, as Chief Secretary for Ireland, he was involved in putting down the Irish Rebellion of 1798 and was instrumental in securing the passage of the Irish Act of Union of 1800.
Robert Stewart was born in Henry Street, Dublin, Ireland, in 1769 the son of Robert Stewart (1739-1821) of Newtownards and Comber in County Down, with properties in Counties Donegal and Londonderry. The family seat was Mount Stewart, County Down.  The elder Stewart was an Irish politician and prominent Ulster landowner He was created Baron Londonderry in 1789, Viscount Castlereagh in 1795, and Earl of Londonderry in 1796 by King George III. In 1771 he was elected in the Whig interest to the Irish House of Commons, where he was a supporter of Lord Charlemont and his allies who called for greater independence from Britain. From the Act of Union of 1800, however, he sat in the British House of Lords as an Irish representative peer. In 1816 he was created Marquess of Londonderry by the Prince Regent.  Stewart's mother, who died in childbirth when he was a year old, was Lady Sarah Frances Seymour-Conway, daughter of Francis Seymour-Conway, 1st Marquess of Hertford (a former British Ambassador to France (1764-65) and Lord Lieutenant of Ireland (1765-66)) and Isabella Fitzroy, daughter of Charles FitzRoy, 2nd Duke of Grafton. His father remarried five years later to Lady Frances Pratt, daughter of Charles Pratt, 1st Earl Camden (1714-94), a leading English jurist and prominent political supporter of both the 1st Earl of Chatham and his son, William Pitt the Younger. Through the elder Stewart's marriages, he linked his family with the upper ranks of English nobility and political elites. The Camden connection was to be especially important for the political careers of both him and his elder son. By Frances Pratt, Stewart's father had ten children who survived to adulthood, including Stewart's half-brother, Charles William Stewart (later Vane), Baron Stewart of Stewart's Court and Ballylawn in County Donegal (1814) and 3rd Marquess of Londonderry (1822).  In 1794, Stewart married Amelia (Emily) Hobart a daughter of John Hobart, 2nd Earl of Buckinghamshire, a former British Ambassador to Russia (1762-65) and Lord Lieutenant of Ireland (1776-80). Her mother, Caroline Conolly, was the granddaughter of William Conolly, Speaker of the Irish House of Commons in the early 18th century and one of the wealthiest landowners in Ireland. Caroline's brother, Thomas Conolly, was married to Louisa Lennox, sister of Emily FitzGerald, Duchess of Leinster, whose son and Emily's cousin-by-marriage, the aristocratic rebel Lord Edward FitzGerald, was a leader of the United Irishmen and one of their martyrs in the early stages of the Irish Rebellion of 1798.  Emily Stewart was well known as a hostess for her husband in both Ireland and London and during some of his most important diplomatic missions. In later years she was a leader of Regency London high society as one of the Lady Patronesses of Almack's. She is noted in contemporary accounts for her attractiveness, volubility and eccentricities. By all accounts, the two remained devoted to each other to the end, but they had no children. The couple did, however, care for the young Frederick Stewart, while his father, Stewart's half-brother, Charles, was serving in the army.
How long did they care for him?
A:
while his father, Stewart's half-brother, Charles, was serving in the army.