The British Royal Family is extensive and vast with numerous family members and relatives going as far back as you can imagine. However, we only seem to concern ourselves with a few popular members for a coupe of reasons. For example, the late Queen, her children, grandchildren and even great grandchildren. This popularity has included the sons-in-law and daughters-in-law that have been married to the princes and princesses.
Some of the most popular members of the British Royal Family include the late Queen Elizabeth, King Charles the new and current monarch, his sons, their wives, children, and other children of the late Queen and their families. Two of some popular member of the royal family are Kate Middleton and Meghan Markle.
It may be a bit confusing to know these two women, and how they happen to be at the center of almost all the news about the royal family. The confusion may be there because they are not often addressed as princesses but just their names. The reason for this is because they are not royals by birth, but by marriage.
Yes, Kate Middleton and Meghan Markle are royals because they are married to a member of the royal family. Kate Middleton is married to Prince William, the current heir apparent and next in line to the throne. This means that Kate is the future queen consort of England. She may not be addressed as Princess, but her official title is Princess of Wales. She is also the Duchess of Cambridge while her husband Prince William is the Prince of Wales and Duke of Cambridge.
On the other hand, Meghan Markle is the wife of Prince Harry, who happens to be the younger brother of Prince William, and is currently fifth in line to the throne after Prince William and hid three children. Like Kate, Meghan is not addressed as princess, but is known as the Duchess of Sussex.
In summary, Kate and Meghan are both daughters-in-law of the new and ruling monarch King Charles as they are married to both of his sons.