fjölskyldu

In a sentence

• Ég eyddi helginni með fjölskyldu minni.

  I spent the weekend with my family.

  In this sentence, "fjölskyldu" is used in the accusative case, referring to the direct object "family" in the phrase "with my family".

• Við borðum kvöldmat saman sem fjölskylda.

  We eat dinner together as a family.

  Here, "fjölskylda" is used in the nominative case to describe the subject functioning equivalently to a collective noun representing 'the family'.

• Ég sakna fjölskyldunnar minnar.

  I miss my family.

  In this case, "fjölskyldunnar" is in the genitive case to show possession, referring to 'my family's' relationship to the action.