Young Family in Killeshandra area in the early 1800's

I am researching the Young family who lived in the townlands of Lahard, Drumgoon and Gartinardress in the early 1800's. I think theywere descended from Richard Young who was agent for Sir Francis Hamilton in the 1660's. Matthew Young was married to Francis Nesbitt in 1730 and their son, James, was married to Jane Nesbitt in 1767. Matthew Young of Lahard, John Young ofDrumgoon and Richard Young of Killeshandra, are recorded as Freeholders in 1761. Cosby Young, born around 1773, married Arabella or Sibella Fleming in 1819. They had 2 daughters, Mary Anne and Jane. Cosby and his wife both seem to have died in 1823/24. Mary Anne later married George Richard Mackerness, while Jane married Henry Meynell. Cosby Young and his family lived in Lahard and the house appears to have been substantial, with formal gardens as can be seen in the ordnance survey maps from the 1830's. At the time of the 1901 and 1911 Census, the house was occupied by Elizabeth Armstrong, widow of James Armstrong who died in 1883. Elizabeth Armstrong died in 1918 and I would like to find out what happened to the house after that. Apart from some of the old boundary walls, there is no trace of the original house, although a later built 2 story house is located there. Mary Ann Mackerness and Jane Young are recorded as Immediate Lessors in several townlands around Killeshandra in Griffiths Valuation, for which their father Cosby was the previous landlord. Their property was later acquired by Robert Hutton, around 1863. Meanwhile, Richard Young of Drumgoon seems to have also owned several townlands in the Killeshandra area in the 1820's. By the early 1840's, the property was owned by William Young, an attorney from Dublin, and his wife Mary Clemina. Most of their lands were sold as an incumbered estate to Robert Hutton, although they still retaineda sizeable farm in Gartinardress, according to Griffiths Valuation. Mary Clemina Young died in 1852 and their son, Walter William died in 1891, but I don't have any information on William, the attorney. I have searched all the normal sources such as birth, death and marriage records, also Killeshandra census for 1841, Griffiths Valuation, Tithes Applotment, etc. My main focusat this stage is to try to establish the various branches of the Young family around the Killeshandra area in the early 1800's, the relationship between Cosby and Richard Young and whether William Young the attorney, was related to them in some way. Also, what became of the big houses in Lahard, Drumgoon and Gartinardress. I would appreciate any bits of information which would help to complete the jigsaw. Our local townlands of Toome, Kilmore and Corbaun in Mullinalaghta parish, Co. Longford, close to Lough Gowna and the boundary with the old civil parish of Killeshandra, were part of the Hamilton estate from the 1660's and were later owned by Cosby and Richard Young.Gerry Matthews.