Jormag and Primordus Kralkatoriks offspring?

[Underdark.3726]

In the last Confer with Bangar achievement Jormag calls Aurene her little sister and Primordus his twin. Does this mean that they are all Kralkatoriks (and/or possibly even Glints) children or do dragons just call themselves brothers and sisters? If Jormag called only Aurene her little sister I wouldn't payed much attantion to it but the twin got me wondering.

[Sajuuk Khar.1509]

There is nothing indicating that the Elder Dragons are directly related to each other. Jormag's comment to Aurene is most likely just figurative due to the fact they are all Elder Dragons.

[Randulf.7614]

And the twin thing is prob just a nod to their link as being each other's weaknesses