According to The Mirror, Manilow urged the Britain's Got Talent runner-up to keep her family and friends around her.
"With Susan Boyle, fame hit her so hard that it kind of knocked her off her feet," he said. "When she appeared on Britain's Got Talent, it was very moving to see what she could do.
"I think she's a good singer, and everyone's very curious to see how far she can go, but speaking from my own personal experiences, I hope she keeps her old friends and family around her."
Manilow explained that people close to him had helped him stay "grounded" and added: "Success can be harder to cope with than failure... There's no school that teaches you how to handle it all."
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