I've always found it so interesting that George III had so many children and barely any legitimate grandchildren. He should have had dozens but so many of his kids died without issue, etc. It is remarkable that Victoria ended up with the crown. I would love to see a movie about Princess Charlotte.
Legitimate is the operative word there, I think. The Prince of Wales had about four illegitimates with various lady loves, and the future William 1V had ten by the actress Dorothea Jordan, for a start. The sons of George III only seemed to be mildly infertile when they married!