Leopold would most certainly not be allowed to become Belgian King, should his son with Charlotte survive: the child would be heir to both Kingdoms, and that would be unacceptable for France and the Netherlands, who, alongside Britain, were the main powers deciding Belgium's fate during the National Congress. Leopold's candidacy wouldn't even be considered.
I doubt Leopold would be forbidden to take his son abroad, should he wish to, at least for short periods.
He would also be named Regent in the case George IV died before the child's adulthood (similar to Victoria and her mother). As father of the future King, George IV would most probably create Leopold a Prince of the United Kingdom, give him a Dukedom and the style ‘Royal Highness’ (the latter was done anyway: King George showed how much he appreciated his son-in-law when he created Leopold “Royal Highness” a year after Princess Charlotte’s death).
If Leopold and Charlotte's son survived and was a healthy baby, there would be no reason for King George's sons to rush into marriages: they were forced to marry because of lack of any Heir. Should the child be sickly or weak, perhaps they would still be forced to marry to produce the 'spare'.
maria-olivia said:
In Belgium we knows that the Princess Charlotte of Wales was really in love with her husband Leopold of SCG. When she would be Queen she said he would be King and not a Prince...Louise Marie accepted to call her Charlotte as the late Princess of Wales
That was certainly a love match, just like Victoria and Albert's marriage. But however much Charlotte loved her husband, she couldn't just make him a King. Even Queen Victoria, who loved Albert just as passionately, achieved nothing more than a "Prince Consort" title for her husband.
The only two times husbands of English Queen Regnant were Kings as well were Philip of Spain (Mary I's husband) and William of Orange (Mary II's husband).
Philip of Spain was a Monarch (his father had to create him King of Naples and titular King of Jerusalem to elevate him to Mary's rank).
Under the terms of the marriage treaty, Philip was to be styled "King of England", all official documents were signed by both of them. However, Philip was never a King Regnant of England: he was styled 'King Philip' because, well, he
was a King (of Naples and Jerusalem, and later, of Spain).
Mary II and William of Orange were invited by the British Parliament to 'conquer' the country (the Glorious Revolution): they were joint Rulers and reigned together as Mary II and William III. They had equal powers. As both were Monarchs in their own right, the one that survived the other was to Reign till his/her death (as it were, William survived Mary). The greatest recognition of William's status came perhaps in the fact that if, following Mary's death, he had children with another woman, those children would be in line of the succession.
Nevertheless, it is important to note that William and Mary were
invited to be joint rulers, and William could claim the Kingship by right of conquest, however peaceful as well (rather like Henry VII, the first Tudor King), so his situation is not comparable with Leopold's.
Leopold might become the true power behind the throne, even the de facto ruler, but I seriously doubt the Parliament would ever consider creating him a King.
I always thought Louise Marie did an extremely selfless and nice thing in deciding to name one of her daughter in honour of her husband's beloved first wife.