Cat Deeley had no idea Ant McPartlin was struggling with drink and prescription drug addiction.
The 40-year-old star reunited with her old 'SM:TV' co-hosts Ant and Dec for a sketch on their show 'Saturday Night Takeaway' earlier this year and she didn't realise there was anything wrong with her old friend - who spent two months in rehab earlier this summer - because he seemed "absolutely fine".
She said: "I didn't know anything. The last time I saw them was in Florida when we did the 'Missing Crown Jewels' thing in Florida in April. Ant seemed absolutely fine."
But the 'Sing' host is proud of Ant for seeking help and she doesn't think his troubles will affect his career, other than to make his fans love him more.
She told Event magazine: "He is doing the right thing. If you need some help, get some help.
"Everybody has issues. He's made the decision to do something about it, which should be applauded. Everybody makes mistakes. Everybody makes some silly choices at some time in their life. We all do it.
"I think he's going to just get better and everyone's going to love him even more for it. They'll love him as much as I do."
Cat - who will reunite with Ant and Dec for an 'SM:TV reunion' next year - admitted she doesn't see the Geordie duo very often, but their friendship is still as strong as ever.
She said: "It's weird, because we won't speak for ages, and then we'll see each other and it's like no time has passed at all.
"'SM:TV' was a moment in all our lives when there was heartbreak and devastation and craziness and good times and that's what makes you the person you are today.
"When you share that with people, no matter how much time goes by, they're a massive part of your life."