1. To attempt to maintain a friendly relationship with someone, especially if that person may be of some benefit or help. I've tried to keep in with the managing editor from my previous job, as she has a lot of useful business contacts from across the state.

2. To have someone or something remain in a particular place with one, someone, or something else. In this usage, a noun or pronoun is used between "keep" and "in." Amelia is petrified of dogs, so you need to keep Rover in with you until she leaves.