Well, (and this is just based on my understanding of how things went down) she was formed from Sora's soul and body, and Kairi's heart. So, kinda? But not really. But kinda? It depends on your definition of parents and children. She's definitely not their child in the traditional or genetic sense, but if your definition of child was "someone formed from and having the characteristics of two different people" or something like that, then maybe. I definitely don't see this way of looking at it being explored in-canon though, nor do I see Sora and Kairi filling those roles for Namine. If you like the idea though that's totally fine to think of it that way, it's an interesting take on it.
Edit: Oh okay lol, you had me there for a minute! But man, that would be one dysfunctional family... (shudders)