Katy Perry's sister saved her from rehab.
The 'Hot N Cold' singer is always accompanied by elder sibling Angela, 26, and says her sister's harsh stance has stopped her spiralling out of control.
She said: "Angela is the one who kicks my a*s. The way she wakes me up is pretty horrible. She'll stand over my face with a glass of cold water and count to three. If I'm not up by three, she'll pour.
"You need 'no' people around you, otherwise you'll end up in rehab. My sister doesn't care how many records I've sold or what I've done or what I have."
Katy also claims her sister is responsible for her success as Angela got her interested in singing at a young age.
She added: "I fell into singing at the age of nine because I was copying everything my sister did. She started having singing lessons and I was like, 'I want them too'. "