The fact that the Duchess of Sussex’s father, Thomas Markle, hasn’t been given a coat of arms has caused a bit of controversy in the tabloid press. The Duchess’s estranged half-sister, Samantha Markle, claims that it is a “huge insult” that her father wasn’t given a coat of arms when the Duchess of Cambridge’s father was. But in reality, there is nothing untoward about this.
Despite what Ms. Markle seems to think, the Royal Family don’t decide whether a private individual should receive a coat of arms. The grants are made in the Queen’s name by the heralds of the College of Arms (for people in England, Wales, and Northern Ireland) or the Court of the Lord Lyon King of Arms (for people in Scotland). Furthermore, arms can only be granted to British citizens, though Americans can receive ‘honorary arms’ if they can prove descent from a British subject. Either way, it’s an expensive proposition: a grant of arms to a private individual costs £6,075 (or a little over $8,000).
Under the law of arms, a man’s arms can be borne by all of his legitimate children, so if Mr. Markle had obtained a coat of arms, the Duchess of Sussex would have been able to use it as well. While the Duchess of Cambridge uses her father’s arms, the heraldic authorities may have felt that this arrangement would be problematic for the Duchess of Sussex since her father’s arms would only be honorary.
Instead, the Duchess has been granted her own coat of arms. Honestly, this seems like the best course of action. The Markles don’t live in the United Kingdom, so it’s hard to see how they would benefit from having an official grant of arms. British heraldic law has no standing in America, so from a legal standpoint, a grant from the College of Arms has no more validity than a certificate of arms bought from a kiosk at the mall.
 The Queen does approve coats of arms granted to members of the Royal Family, but her involvement there is the exception rather than the rule.
 The College of Arms also serves other Commonwealth countries that do not have their own heraldic authorities.
 However, a daughter cannot pass her father’s arms onto her children unless a) she has no brothers or b) all of her brothers have died without surviving issue.