Is April a peer or a mother figure to the Turtles?

[Spike Spiegel]

I was thinking about the family dynamic of TMNT across the incarnations and this thought crossed my mind.

I think in Mirage/the 2003 show/the 1990s movies especially, it's a little of both. But if they met, say, Casey first, or they never met her at all, would the story and relationship dynamics be all that different?

They're starting their lives as she is starting her career, so they can be seen as peers in that way. But at the same time, she is technically older than them.