Patient care devices, such as person support apparatuses and thermal control units, include multiple internal network nodes. A controller is associated with each node and at least one of the controllers is adapted to process a message received from another node, convert the message from a first communication protocol to a different communication protocol, and forward the message to yet another node using the different communication protocol. One or more of the controllers may also or alternatively reformulate a packet received in a first format from a first node and forward the reformulated packet to another node. One or more controllers may also send messages over a common data link layer wherein some of the messages are formatted according to different message protocols. Some controllers may utilize real time operating systems while others may not.