Illegitimate parent, more likely. English is clearly the bastard child here, with its Celtic, French and Norwegian influences.

I also once heard that Dutch uses older roots of many words than German, because for many words where Dutch uses an 'i' (like "ieder"), German uses a 'j' ("jeder"), which is a more recent letter.

Well there are no parents or children in extant languages of course, only closest common ancestors.

Dutch is much more in the middle between German and English while those two are at the edges of west Germanic languages, hence the joke

Dutch is to German like Danish is to Swedish, in the sense that it's easier to understand more from reading Dutch if you're a German-speaker, or Danish if you're a Swedish-speaker, than hearing them spoken. The pronunciation of Dutch and Danish feels like "almost intelligible, except it sounds so guttural, as if they have their mouths full of gravel and porridge". The written text is the same thing as the spoken, except much clearer, because you can see the letters where you can't hear the sounds.

I believe that dutch was invented when interdimensional dragon interlopers tried to learn "human language" but got an assortment of English, German, and French books without knowing they were different languages.