heir

Someone who inherits, or is designated to inherit, the property of another.

My brother is the heir to our childhood house and yet has no interest in it.

I am my father's heir and only son.

One who inherits, or has been designated to inherit, a hereditary title or office.

As the heir to the British throne, the Prince of Wales is a very public figure.

Now, after the death of Queen Elizabeth II, William, 40, is the Prince of Wales and the heir to the British throne.

A successor in a role, representing continuity with the predecessor.

And I his heir in misery alone.

"I wish we were back in Tenth Street. But so many children came[…]and the Tenth Street house wasn't half big enough; and a dreadful speculative builder built this house and persuaded Austin to buy it. Oh, dear, and here we are among the rich and great; and the steel kings and copper kings and oil kings and their heirs and dauphins.[…]"

To inherit.

[…] Leonard Houtz & John Myer to be executors to this my last will & testament & lastly my children shall heir equally, one as much as the other.