[dalke]

"And "arlskling" isn't a million miles away from "darling"."

It is, however, a million kilometers away. The "-ling" suffix here is from Old English, and was used in personal nouns. "Dēorling" is "dear-ling", or one who is dear. In modern English it's often used as a diminutive. (Eg, "duckling", "hireling".)

The "-ling" suffix also exists in other Germanic languages. For example, "Yuengling" is a brewing company in the US. Its name comes from "an Anglicized version of Jüngling, its founder's surname and the German term for 'young man'." (So says Wikipedia.)

The Swedish "älskling" comes from the verb "älska" (to love) and the same suffix. One page describes the suffix as "ordbildningsform som användes i fornsvenskan för att uttrycka litenhet", that is, a "word formation used in Old Swedish to express smallness", in other words: in the diminutive.

So while "darling" and "arlskling" end the same, it's because both language share a similar "-ling" mechanism.

The base word ("dar" and "älsk") have different background. The "dar" is from "dear", and the Swedish cognate for dear is "dry", which means "expensive" in modern Swedish. Consider "the price was too dear for me.")

That's why you shouldn't think of "älskling" and "darling" as being related words. They are as related as "yuengling" and "duckling", which isn't very.

[gadders]

Bad example then. But the suffixes are related?

[dalke]

I believe so. I researched it a bit more. According to http://www.etymonline.com/index.php?term=-ling&allowed_i... , which is a better resource than the sites I found earlier, it comes from Old English, meaning " 'person or thing of a specific kind or origin;' in masculine nouns also 'son of' (cf. farthing, atheling, O.E. horing 'adulterer, fornicator')."

It further clarifies: "Both these suffixes had occasional diminutive force, but this was only slightly evident in O.E. -ling and its equivalents in Germanic languages except Norse, where it commonly was used as a diminutive suffix, especially in words designating the young of animals (e.g. gæslingr "gosling"). Thus it is possible that the diminutive use that developed in Middle English is from Old Norse."

It appears then that "-ling" in Old English meant "person or thing of a specific kind or origin", which it shared with other Germanic languages, and grew to acquire the diminutive use after the Old Norse influence on English.