Vigtige sounds like wichtig in German!
Surely you could take into account 'brothers and sisters' as well as 'siblings'!
Well, that would be brødre og søstre, not søskende.
Do you just have to memorize that it has an e at the end, or is there a pattern/rule?
"It"? There are three words that end on -e in this four-word sentence. Two of them (mine and vigtige) end on -e because the other one (søskende) does, too. These adjectives are reflecting that the noun is plural.
Yeah, I'm referring to "vigtige." I'm having a hard time remembering when I should put an "e" at the end of it in differing contexts. So the reason is because of the plurality of the noun?
Yes, precisely. Vigtig describes søskende (they are all important), so it has to match the noun and is put in the plural form as well.