@JohnK Ahh thanks for letting us know. this is new to me. Have you through about making it a network game instead so the other user can use his own PC, I hate touching my brothers keyboard… 
Look at the Lidgren network library that is shipped with monogame, it looks really easy to use/learn and might be the ideal solution for you (still learning it myself).
as for Mouse, it’s Mouse for one and Mice for multiple.