How would you write my redheaded one in Gaelic?

There isn't a single perfect translation for "my redheaded one" in Gaelic, as the best option depends on which Gaelic language (Scottish Gaelic or Irish Gaelic) you prefer and the level of formality. Also, the nuance of endearment can be expressed in different ways.

Here are a few options:

Scottish Gaelic:

* A ghaoil ruaidh: This is probably the closest and most natural-sounding translation. "A ghaoil" means "my love" and "ruaidh" means red/red-haired. It's affectionate and fairly informal.

* Mo leannan ruaidh: This translates to "my sweetheart/lover red-haired," again fairly informal and affectionate. "Leannan" implies a romantic relationship.

Irish Gaelic:

* A stór rua: "A stór" means "my treasure" or "my darling," and "rua" means red/red-haired. This is very affectionate and informal.

* Mo chroí rua: This translates to "my heart red-haired." "Mo chroí" means "my heart" and implies deep affection.

Considerations:

* Gender: The above examples are gender-neutral in their affection. If you need to specify a male or female, you would need to adjust the possessive pronoun ("mo" or "a") and possibly the term of endearment. For example, "mo chroí rua" would work for either male or female.

Ultimately, the best translation depends on the context and the desired level of intimacy. "A ghaoil ruaidh" (Scottish Gaelic) or "A stór rua" (Irish Gaelic) are likely good starting points for most situations.