I seriously doubt it's real because a mom who wanted her baby to stay secret would never write that. And if she didn't want it to stay secret, then she'd just contact a paternity lawyer, not make a stupid note on the Internet.
Here's the thing: I personally know someone who DID have a baby with a very high-profile 80s rock star. There was no doubt it was his. But she didn't want him to know about it because in their short time of being together he treated her badly and she didn't want that kind of life for the baby. She didn't want his money, because that would have meant he'd get visitation rights. So the only people who know are very close family. It's a problem sometimes because now that he's older he looks just like his dad, but she just keeps denying it.