The Saturdays singer is getting lots of advice from her friend - who had her first child, Aoife, with her rugby player husband Ben Foden last March - in preparation for when she gives birth later this year.
Rochelle said: ''I can always ask her questions, and that helps. She's given me lots of tips.''
Despite being pregnant, Rochelle hasn't slowed down in her career or at home, even though she has had days where she has felt really tired.
Speaking to the latest issue of new! magazine, she explained: ''I think it's natural that you get more tired than usual, but I've got a really strong work ethic so I haven't allowed it to hold me back.
''I do what I can do, but if I feel tired I'm sensible and have a lie down. But I haven't had a day off since I've been pregnant.''
The 23-year-old pop star also says her pregnancy has brought her and her husband, JLS member Marvin Humes, closer together.
She added: ''We're together a lot. We've always been close, but this experience has brought us even closer. Marvin is very good at looking after me and he's been great throughout the pregnancy. I'm very lucky to have that support behind me. He's always looking out for me, it's so nice.''