Difference between Heir Presumptive and Imperturbable

HEIR PRESUMPTIVE vs IMPERTURBABLE: NOUN

Someone who will inherit only if no better choice for an heir is born.
See heir apparent.
An heir who stands to inherit the estate, title, or office of an intestate ancestor, but whose claim can be defeated if a relative who is closer to the ancestor is born prior to the ancestor's death.
A person who expects to inherit but whose right can be defeated by the birth of a nearer relative

Succession, Peacock throne, Kingship, Dynastic, King, Prince consort, Princeling, Monarch, Figurehead, Prince regent, Coronation, Heir, Successor, Throne, Heir apparent

Diffident, Affable, Amiable, Phlegmatic, Unexcitable, Undemonstrative, Stoic, Taciturn, Stolid, Impassive, Unruffled, Unshaken, Sedate, Composed, Unflappable

Succession, Peacock throne, Kingship, Dynastic, King, Prince consort, Princeling, Monarch, Figurehead, Prince regent, Coronation, Heir, Successor, Throne, Heir apparent

Diffident, Affable, Amiable, Phlegmatic, Unexcitable, Undemonstrative, Stoic, Taciturn, Stolid, Impassive, Unruffled, Unshaken, Sedate, Composed, Unflappable

He is the son of Eliwood, the main character of Fire Emblem: The Blazing Blade, and heir presumptive of Pherae.
Frenchman, that he is not heir presumptive to another crown, and that he has previously taken the civic oath.
Prince Albert became King George VI and the young Princess Elizabeth became heir presumptive to the throne.
Known as "The Brat" in the Heraldic Circle, the Heir-presumptive lives up to her nickname.
Roger was made lieutenant of Ireland and was declared heir presumptive to the Crown.

Neurologists are imperturbable as well, but our children's hospital and having potassium cyanide as a major symptom.
The whole city, inman brain and imperturbable nerve that even boys can teach themselves the are wed.
I also remember him as the coolest man I ever saw, absolutely imperturbable.
He remained august and imperturbable, but I realized that this new arrival was not on his side.
Avi, imperturbable as usual, answered for his partner, gesturing to the group of young men around him.
Rather than the angry Jesus, Luke portrays an imperturbable Jesus.
This type is typically not angry and is often imperturbable.
En la vereda de enfrente, el verdulero Lamensa, imperturbable, hizo arrancar su camioneta.
Painters followed poets, but sculpture stayed almost imperturbable in its marble serenity.
Before their imperturbable jocundity what bad humour can exist?