Their son Vilhelm Bjerknes was born in 1862 and he played an important role in his father's work both as an assistant to his father when he was young, then later writing up his father's hydrodynamical work for publication.
Ang kanilang mga anak na lalaki Vilhelm Bjerknes ay ipinanganak sa 1862 at maririnig siya ng isang mahalagang papel sa kanyang ama gawain parehong bilang isang assistant sa kanyang ama kapag siya ay bata, at saka sa huli ay sumusulat up ng kanyang ama hydrodynamical trabaho para sa publikasyon.