No you don't. Here are the official rules

Rule 4.2 - Serve, in Doubles
a. Server: At the beginning of each game in doubles, each side shall inform the referee of the order of service, which order shall be followed throughout the game. Only the first server serves the first time up and continues to serve throughout the game. When the first server is out, the side is out and this applies in each game throughout the match. Thereafter both players on each side shall serve until a handout occurs. It is not necessary for the server to alternate serves to their opponents.
b. Partner's Position: On each serve, the server's partner shall stand erect with his back to the side wall and with both feet on the floor within the service box until the served ball passes the short line. Violations are called "foot faults". For wheelchair racquetball, the server's partner musthave at lease one rear wheel in the service box until the served ball passes the short line. Violations are called "wheel faults".