The couple were married in Dublin near to Helen’s family residence of Upper Merrion Street, she was the 6th child of Edward Micheal Pakenham, Ist Earl Longford and Catherine Rowley.

Her siblings were:

1. Elizabeth Pakenham: 1769 - 1851 m Henry Stewart of Tyrcallen, Co. Tyrone

2.Mary Pakenham: 1770 - 1787

3. Catherine (Kitty) Sarah Dorothea Pakenham: 1772 – 1831 m Arthur Wellesley Ist Duke of Wellington

4. Frances Pakenham: 1773 – 1774

5. Thomas Pakenham (2nd Earl Longford): 1774 – 1835 m Georgiana Emma Charlotte Lygon

6. Gen Sir Edward Micheal Pakenham: 1778 – 1815

7. Caroline Penelope Pakenham: 1780 – ? m Henry Hamilton

8. Maj. Gen. Sir Hercules Rowley Pakenham: 1781 – 1850 m Emily Stapleton

9. Capt. William Pakenham: 1782 – 1811

10. Henry Pakenham: 1787 – 1863 m Eliza Catherine Sandford

James Hamilton had inherited the estate of Brownhall from his father John and the couple took up residence after their marriage, though they divided their time between the estate in Co Donegal and Dublin. During their absence John’s brother Abraham and his family occupied the house of Brownhall.

The couple had three children:

1. John Hamilton: 1800 – 1884

2. The Rev. Edward Micheal Hamilton: 1802 – 1861 m Martha Anne Fortescue

3. Catherine Hamilton: 1803 – 1871 m Rev. William Henry Foster of Loughgilly

The marriage was tragically brief with James dying at the age of 30 in 1805. Helen died two years later and the care of the three children was taken over by Helen’s sister Catherine Wellesley (later Duchess of Wellington), their maternal grandmother Lady Longford and their paternal grandmother Isabella (Stewart) Hamilton. Within a short time the children were cared for full-time by the Pakenham family due to the advanced age of their much loved grandmother Isabella and the more beneficial surrounds of Dublin.

With John being the eldest (and heir to Brownhall ) his uncle Arthur Wellesley, then Chief Secretary for Ireland, took particular interest in his education and saw that he eventually attended Cambridge University in England. Through this John was granted his Degree after just 2 years due to a very old law which stated that direct male descendants of the Monarch could gain their qualification in a shorter time. John, of course, was descended from King Edward Ist .

John Hamilton would later recall with great affection and gratitude the loving environment into which he and his orphaned siblings were accepted into by his mother Helen’s family. His little sister Catherine, named for their mother’s sister, would grow to be extremely close to the woman later known as ‘Kitty’ Wellington – and she too in turn would be known by the name Kitty throughout her life.