Kivilaan's arrival jeopardised Vanilla Ninja's participation in the Contest, as she was only 15 years old, and after the appearance of young participants such as 1986 winner Sandra Kim, the Eurovision had set an age requirement that all participants must be at least 16.
She had been modelling for several years when she replaced Maarja Kivi on bass in the group in 2004, having met the other members of the group a year earlier.
Kivilaan also only appeared sparingly in the group's music videos, with the exception of "When The Indians Cry", in which she featured prominently.
Kivilaan was by several years the youngest member of the group, and continued with her education despite Vanilla Ninja's busy schedule.
The reasons given by the group when announcing the decision was that Kivilaan had left by "mutual consent", and that creative differences were the main reason for her leaving.
After leaving Vanilla Ninja, Triinu expressed a desire to return to the music industry once she completes her studies, as a solo artist.