There would still be a lot of things that you and your friend would experience. There would still be a lot of things that you’d be learning. Just like learning, it never stops. Don’t put an end to what you know about them, instead, expand it, know them better. May it be their new favorite movie, or their new favorite band. Know it.
There’s always room for something new. Be all ears when they talk about their newest favorite author or book, or even their new favorite basketball star. Anything under the sun. It’d lead to better paths to making the friendship last long and evergreen.