Mum-of-two Lily was among the thousands of fans crammed into the London venue on Tuesday (6 May) to watch Miley kick off the European leg of her 'Bangerz Tour'.
And while there were plenty of raised eyebrows this morning about Miley's stage antics and swearing, Lily said she'd thoroughly enjoyed the evening.
"She has been doing it for so long, since she was about two, so she has this presence that is so natural and not forced," she told ITV's Loose Women.
"Brilliant and funny and entertaining. Yes, there was a lot of swearing and inappropriate stuff going on but she's Miley Cyrus and you know what will happen."
"She was legendary last night," she added. "It was by far the best show I've seen at the O2."
Lily - who was two young daughters - admitted she'd seen parents with young children among the audience but suggested Miley wouldn't be a bad influence on those children if their parents spoke with them about the show.
"It was quite extreme but I think if you can talk to your kids and explain to them afterwards that maybe she's being a bit silly and showing off and that's not how you should behave."
Lily said she had an issue with sex appeal in music or pop culture when someone is told they have to do something that they don't want to, but it's a different issue when the performer in question wants to strip off or behave seductively.
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