Question: What singer born in London in 1988 joined The Voice as a new judge in 2015?
Sentence (from "The Voice (Australia season 4)"): On 13 January 2015, it was announced that Delta Goodrem would return to the panel, and new judges Jessie J and Benji Madden would join the series, replacing former judges Kylie Minogue and will.i.am.
Relevant evidence: Yes