fluent does not stop child processes

[sohaibmaroof]

Hi, I am trying to use in_multiprocess plugin, it works fine and can start child fluentd processe, but it does not stop it when I try to stop the parent fluentd process from fluentd-ui
Just trying to test it by setting up one child fluentd

Here are my config files:
Parent fluend.conf

<source>
  @type multiprocess
  <process>
    cmdline -c ./Users/sohaib.maroof/.fluentd-ui/fluentd_child1/fluent.conf --daemon ./Users/sohaib.maroof/.fluentd-ui/fluentd_child1/fluent.pid --log ./Users/sohaib.maroof/.fluentd-ui/fluentd_child1/fluent.log
  </process>
</source>

Child fluentd.conf

<source>
  @type forward
  port 24224
</source>

<filter **.*>
  @type stdout
</filter>

 <match *.**>
    @type elasticsearch_dynamic
    #elasticsearch host IP/domain
    hosts "es_host"
    index_name fluentd-${tag_parts[1]}
    buffer_chunk_limit 9MB
    flush_interval 1s
    #buffer_chunk_size 1MB
    buffer_type memory
    chunk_limit_size 9MB
    num_threads 20
</match>

[sohaibmaroof]

@repeatedly can you please help me figure out the issue?