This is how I believe a Remus a Sirius got together and it does go up until book 7. Which means there is book moments too.
Year 1
James, Sirius and Peter all become mga kaibigan at the start of term feast. (Well actually just Peter becomes they're friend but you get the point.) Remus doesn't befriend them until later that taon but he is already mga kaibigan with Lily. When they do become mga kaibigan Remus is instantly nalugod sa pamamagitan ng Sirius.
Year 2
(Near end of year) James, Sirius and Peter find out about Remus' condition. Which of course we know that they still want to be his friend.
Year 4
Remus stars to develop...