This person will have a serious, sobering effect on you. If you're in a less established position in life than they are, they won't be able to resist offering you plenty of comments and suggestions about how to get on the right track. The problem is, this can come across as meddling or criticism, especially since they're already naturally the more authoritative one in this friendship.
Duty and responsibility will weigh heavily on you, and there will be times when your buddy will seem like a real drag. Still, you might come to depend on them for advice and solid support. It could be a real relief to have a friendship with someone you'll know instinctively that you can trust. You can decide to be open to the advice they give you and to offer your own valuable perspective in exchange. It all depends on how you to look at it.