Need Help to write batch file which executes another bat file if its exsists and not running

Question

Suppose I have a bat file named parent.bat which looks like

@ECHO off
rem this is parent.bat file
:label
if exist child1.bat (
tasklist /v /fi "IMAGENAME eq cmd.exe"|find /I /c "hello1"
if %ERRORLEVEL% == "0" start child1.exe
)
if exist child2.bat (
tasklist /v /fi "IMAGENAME eq cmd.exe"|find /I /c "hello2"
if %ERRORLEVEL% == "0" start child2.exe
)
if exist child3.bat (
tasklist /v /fi "IMAGENAME eq cmd.exe"|find /I /c "hello3"
if %ERRORLEVEL% == "0" start child3.exe
)
timeout /t 120
goto label

I have child1.bat as

  @ECHO off
  title hello1
  start www.google.com
  timeout /t -1

I have child2.bat as

  @ECHO off
  title hello2
  start www.yahoo.com
  timeout /t -1

I have child3.bat as

  @ECHO off
  title hello3
  start www.facebook.com
  timeout /t -1

My intention is to run facebook,google,yahoo if the child.bat files exist and they are not running

but what happens is even if the child.bat files are running (they are in paused mode) the parent.bat file opens all the child.bat files

Even more some times when i change the qoutes in %ERRORLEVEL% == "0" it does not start child1.bat and child2.bat

sometimes the opposite and sometimes child2.bat and child3.bat are started

Answer 1

:label
for %%f in (1 2 3) do if exist "child%%f.bat" (
    tasklist /v /fi "IMAGENAME eq cmd.exe"|findstr /I "hello%%f" >nul 
    if errorlevel 1 start "child%%f.bat"
)
timeout /t 120
goto :label