[quote=""Mythica""]Regarding the succession, I've always wondered what would happen if William and Kate couldn't have children but adopted? Traditionally, I would assume that not being of the royal bloodline, they would not be able to succeed - but today, that would be so hugely politically incorrect because it suggests that an adopted child is not their "real" child. Ethically, should an adopted child be able to inherit the throne?[/quote]
According the the
Act of Settlement of 1701, the monarch must be the Protestant heir of Electress Sophia of Hanover, granddaughter of King James I. This act was prompted by the failure of William III/Mary II and Queen Anne to have heirs and is still in effect. If William did not have children, the throne would go to Harry and his heirs, and so on. While there is a limit to the number of those in the line of succession (the Protestant descendants of Electress Sophia who have not married Catholics), there is no shortage. There are thousands of Protestant descendants of Electress Sophia. The following is just the descendants of King George V, the present Queen's grandfather who died in 1936.
1. HRH The Prince Charles, The Prince of Wales (1948), eldest son of HM Queen Elizabeth II
2. HRH Prince William, The Duke of Cambridge (1982), elder son of HRH The Prince Charles, The Prince of Wales
3. HRH Prince Henry of Wales (1984), younger son of HRH The Prince Charles, The Prince of Wales
4. HRH The Prince Andrew, The Duke of York (1960), second son of HM Queen Elizabeth II
5. HRH Princess Beatrice of York (1988), elder daughter of HRH The Prince Andrew, The Duke of York
6. HRH Princess Eugenie of York (1990), younger daughter of HRH The Prince Andrew, The Duke of York
7. HRH The Prince Edward, The Earl of Wessex (1964), youngest son of HM Queen Elizabeth II
8. James Windsor, Viscount Severn (2007), son of HRH The Prince Edward, The Earl of Wessex
9. Lady Louise Windsor (2003), daughter of HRH The Prince Edward, The Earl of Wessex
10. HRH The Princess Anne, The Princess Royal (1950), only daughter of HM Queen Elizabeth II
11. Peter Phillips (1977), son of HRH The Princess Anne, The Princess Royal
12. Savannah Phillips (2010), daughter of Peter Phillips
13. Isla Phillips (2012), daughter of Peter Phillips
14. Zara Phillips (1981), daughter of HRH The Princess Anne, The Princess Royal
15. David Armstrong-Jones, Viscount Linley (1961), son of HRH The Princess Margaret, Countess of Snowdon
16. The Honorable Charles Armstrong-Jones (1999), son of David Armstrong-Jones, Viscount Linley
17. The Honorable Margarita Armstrong-Jones (2002), daughter of David Armstrong-Jones, Viscount Linley
18. Lady Sarah Chatto (1964), daughter of HRH The Princess Margaret, Countess of Snowdon
19. Samuel Chatto (1996), son of Lady Sarah Chatto
20. Arthur Chatto (1999), son of Lady Sarah Chatto
21. HRH Prince Richard, The Duke of Gloucester (1944), son of HRH The Prince Henry, Duke of Gloucester, 3rd son of HM King George V
22. Alexander Windsor, Earl of Ulster (1974), son of HRH Prince Richard, Duke of Gloucester
23. Xan Windsor, Lord Culloden (2007), son of Alexander Windsor, Earl of Ulster
24. Lady Cosima Windsor (2010), daughter of Alexander Windsor, Earl of Ulster
25. Lady Davina Lewis (1977), daughter of HRH Prince Richard, Duke of Gloucester
26. Tāne Mahuta Lewis (2012), son of Lady Davina Lewis
27. Senna Lewis (2010), daughter of Lady Davina Lewis
28. Lady Rose Gilman(1980), daughter of HRH Prince Richard, Duke of Gloucester
29. Lyla Gilman (2010), daughter of Lady Rose Gilman
30. HRH Prince Edward, The Duke of Kent (1935), son of HRH The Prince George, Duke of Kent, fourth son of HM King George V
--- George Windsor, Earl of St. Andrews (1962), son of HRH Prince Edward, The Duke of Kent - excluded himself from the succession by marrying a Roman Catholic
--- Edward Windsor, Baron Downpatrick (1988), son of George Windsor, Earl of St. Andrews - excluded himself from the succession by becoming a Roman Catholic
--- Lady Marina-Charlotte Windsor (1992), daughter of George Windsor, Earl of St. Andrews - excluded herself from the succession by becoming a Roman Catholic
31. Lady Amelia Windsor (1995), daughter of George Windsor, Earl of St Andrews
--- Lord Nicholas Windsor (1970), son of HRH Prince Edward, The Duke of Kent - excluded himself from the succession by becoming a Roman Catholic
32. Albert Windsor (2007), son of Lord Nicholas Windsor
33. Leopold Windsor (2009), son of Lord Nicholas Windsor
34. Lady Helen Taylor (1964), daughter of HRH Prince Edward, The Duke of Kent
35. Columbus Taylor (1994), son of Lady Helen Taylor
36. Cassius Taylor (1996), son of Lady Helen Taylor
37. Eloise Taylor (2003), daughter of Lady Helen Taylor
38. Estella Taylor (2004), daughter of Lady Helen Taylor
--- HRH Prince Michael of Kent (1942), son of HRH The Prince George, The Duke of Kent - excluded himself from the succession by marrying a Roman Catholic
39. Lord Frederick Windsor (1979), son of HRH Prince Michael of Kent
40. Lady Gabriella Windsor (1981), daughter of HRH of Prince Michael of Kent
41. HRH Princess Alexandra, The Honourable Lady Ogilvy (1936), daughter of HRH The Prince George, Duke of Kent
42. James Ogilvy (1964), son of HRH Princess Alexandra
43. Alexander Ogilvy (1996), son of James Ogilvy
44. Flora Ogilvy (1994), daughter of James Ogilvy
45. Marina Ogilvy (1966), daughter of HRH Princess Alexandra
46. Christian Mowatt (1993), son of Marina Ogilvy
47. Zenouska Mowatt (1990), daughter of Marina Ogilvy
48. David Lascelles, 8th Earl of Harewood (1950), son of George Lascelles, 7th Earl of Harewood
49. Alexander Lascelles, Viscount Lascelles (1980), son of David Lascelles, 8th Earl of Harewood
50. The Honorable Edward Lascelles (1982), son of David Lascelles, 8th Earl of Harewood
51. The Honorable James Lascelles (1953), son of George Lascelles, 7th Earl of Harewood
52. Rowan Lascelles (1977), son of James Lascelles
53. Tewa Lascelles (1985), son of James Lascelles
54. Sophie Lascelles (1973), daughter of James Lascelles
55. The Honorable Jeremy Lascelles (1955), son of George Lascelles, 7th Earl of Harewood
56. Thomas Lascelles (1982), son of Jeremy Lascelles
57. Ellen Lascelles (1984), daughter of Jeremy Lascelles
58. Amy Lascelles (1986), daughter of Jeremy Lascelles
59. Tallulah Lascelles (2005), daughter of Jeremy Lascelles
60. Henry Lascelles (1953), son of The Honorable Gerald Lascelles (younger son of HRH The Princess Mary, The Princess Royal)
61. Maximilian Lascelles (1991), son of Henry Lascelles