Checking child process status in Perl -

i'm having trouble getting exit status of child processes. reason kill 0, $pid way doesn't seem work. i'm running following script on unix machine:

for ( $count = 1; $count <= 2; $count++) {     $pid = fork();     if ($pid) {     # parent     push(@childs, $pid);     } elsif ($pid == 0) {             # child             sleep(10);             exit 0;     } else {             die "couldnt fork: $!\n";     } 

}

foreach (@childs) {  if (kill 0, $_){     print "$_ running...\n"; } else {     print "$_ complete\n"; } 

}

sleep (20); foreach (@childs) { if (kill 0, $_){     print "$_ running...\n"; } else {     print "$_ complete\n"; } 

}

the prints are:
23285 running...
23286 running...
23285 running...
23286 running...

can please explain why won't work, , maybe suggest solution or workaround ?
many thanks!

whenever need fork 1 child , wait use wait() function.

when have fork multiple children , wait them, use parallel::forkmanager module.