Is there any way that one of the Postgres Background/Utility process may go down?

Is there any way that one of the Postgres Background process may go down?
meaning the process getting stopped?

For example, can the wal sender process alone stop working? If it does so,
which part of the logs I must check to proceed further.

-----
--
Thanks,
Rajan.
--
Sent from: http://www.postgresql-archive.org/PostgreSQL-hackers-f1928748.html