Forewarning that this story will contain a lot of OC's. If that's not your cup of tea, you know what to do. If you're still curious, here's a master list of characters. I know this is unconventional but bear with me. Hopefully this method will decrease the amount of 'wait, who?' going on.
James Potter x Lily Evans
Harry (1980), Jack (1982), Mia (1985)
William Granger x Miranda
Hermione (1980), Lavinia (1984)
Sirius Black x Marlene McKinnon
Phoebe (1985), Leo (1987)
Remus Lupin x Hestia Jones
Tiberius (1987), Demetra (1989)
Peter Pettigrew x Mary MacDonald
Julie (1989), Jenna (1991)