WAL receive process dies

We have a periodic network connectivity issue (unrelated to Postgres) that
is causing the replication to fail.

We are running Postgres 9.3 using streaming replication. We also have WAL
archives available to be replayed with restore_command. Typically when I
bring up a slave it copies over WAL archives for a while before connecting
via streaming replication.

When I notice the machine is behind in replication, I also notice that the
WAL receiver process has died. There didn't seem to be any information in
the logs about it. The solution thus far has been to restart Postgres. I
have two questions:

1. It seems that Postgres does not fall back to copying WAL archives with
its restore_command. I just want to confirm that this is what Postgres is
supposed to do when its connection via streaming replication times out.
2. Is it possible to restart replication after the WAL receiver process has
died without restarting Postgres?

Thanks!
Patrick