United Kingdom, Feb. 20 -- Hilary Duff has confirmed her devastating rift with sister Haylie Duff.

The 38-year-old singer is estranged from her older sibling Haylie - who had a guest role in Hilary's breakout TV hit Lizzie McGuire - and Hilary admitted that no longer having a relationship with her sister is "the most lonely part of my existence".

Speaking on CBS Mornings, Hilary confirmed the song We Don't Talk is about Haylie and said: "It's definitely about my sister. And just absolutely the most lonely part of my existence is not having my sister in my life at the moment."

Former Disney Channel star Hilary went on to say that she has no idea what Haylie will think of the track but she wanted to include it on her new record luck. or ...