Saanen made some really good points. I think it would be great to just jump right in with the ideas you are having, but it would all depend on the interaction. Because, like Saanen said, you could be missing out on some characterization opps.
If I find myself facing your dilemna, I would usually sit down and do a few 10 minute writing exercises to try to generate some ideas. What you write during these exercises doesn't have to be used in the WIP, just use them as jumping off points to get to know your characters better. I also do on-the-spot diary entries, putting myself into the headspace of a potential or known character. That way all this stuff comes out about the character...it's like the character is telling you about themself. Again, the writing I do in diary entries isn't used in my WIP, just used as a background to better understand my characters.
I would also ask myself if the other generation are needed. It sounds, from the little you said, that they would be. It sounds like you are looking at the older generation being half the content...but I could be wrong. Hope some of this helps.