The Saturdays singer found she developed her parenting skills through ''instinct'' when she had daughter Aoife Belle 11 months ago, and though she thinks her bandmate - whose first child with JLS star husband Marvin Humes is due in July - will do the same, she will always be on hand to give advice if she needs to.
She said: ''I haven't given any specific advice to Rochelle. When I had Aoife, I didn't have a clue. I hadn't changed a nappy in my life. You learn from instinct.
''Every mother is different, every baby is different. But Rochelle went through it all with me, so I'll always be there for her.''
Una and her husband Ben Foden are keen to have siblings for their daughter, but she insists it won't be in the near future.
She told Closer magazine: ''I do want more kids, but not for a few years.''