The American Idol judge said that whilst pregnant with twins Max and Emme, people insisted on forcing their opinions on her.
She told OK, 'Everybody gives you a lot of advice when you are pregnant, which I find a tiny bit annoying, so I'm not going to give any.
'But I did read What To Expect When You Are Expecting by Heidi Murkoff and Sharon Mazel. You can go day-by-day with that. It's awesome.'
The 41-year-old admitted that she initially expected her son and daughter to get on more than they did.
She added, 'They're starting to play with each other more but there was a time when they were really fighting, a lot.
'He wouldn't mean it, but he would push her and she would get upset and try to bite him. They were like battling it out for position.
'Now they hold hands and walk around - it's very cute. They're lovely together and they give each other hugs and kisses.'