PHP processes

I just wanted to check a technical point with the list. Apache uses the following technique to manage requests from clients Apache starts master process Master process starts x number of childen processes which handle requests from web clients Number of children processes is increased/decreased depending on web server load If PHP is configured to run as a module inside Apache, does an instance of PHP get created for each child process? I ask this question due to stability issues. If Apache crashes you lose one request. If a PHP instance crashes, does it take down only the child process it is associated with, or will one crash in a PHP instance, stop all other instances from operating correctly (until the web server is restarted) Thanks for your time, Ashley