Node process not being killed properly when WPF closes

C#
public void MainWindow_Closed(object sender, EventArgs e)
{
    try
    {
        Console.WriteLine("Closing application...");

        // Kill all child processes
        foreach (var childProcess in _ChildProcesses)
        {
            Console.WriteLine($"Killing child process with PID: {childProcess.Id}");
            if (!childProcess.HasExited)
            {
                childProcess.Kill();
                childProcess.WaitForExit();  // Ensure it exits
            }
        }

        // Kill the main client process
        if (_Client != null && !_Client.HasExited)
        {
            Console.WriteLine($"Killing client process with PID: {_Client.Id}");
            _Client.Kill();
            _Client.WaitForExit();
        }

        // Kill the main server process
        if (_Server != null && !_Server.HasExited)
        {
            Console.WriteLine($"Killing server process with PID: {_Server.Id}");
            _Server.Kill();
            _Server.WaitForExit();  // Ensure the server process exits
        }

        // Graceful shutdown
        Application.Current.Shutdown();
    }
    catch (Exception ex)
    {
        MessageBox.Show($"Error while closing: {ex.Message}");
    }
}

C#
public void MainWindow_Closed(object sender, EventArgs e)
{
    try
    {
        Console.WriteLine("Closing application...");

        // Kill all child processes
        foreach (var childProcess in _ChildProcesses)
        {
            Console.WriteLine($"Killing child process with PID: {childProcess.Id}");
            if (!childProcess.HasExited)
            {
                childProcess.Kill();
                childProcess.WaitForExit();  // Ensure it exits
            }
        }

        // Kill the main client process
        if (_Client != null && !_Client.HasExited)
        {
            Console.WriteLine($"Killing client process with PID: {_Client.Id}");
            _Client.Kill();
            _Client.WaitForExit();
        }

        // Kill the main server process
        if (_Server != null && !_Server.HasExited)
        {
            Console.WriteLine($"Killing server process with PID: {_Server.Id}");
            _Server.Kill();
            _Server.WaitForExit();  // Ensure the server process exits
        }

        // Graceful shutdown
        Application.Current.Shutdown();
    }
    catch (Exception ex)
    {
        MessageBox.Show($"Error while closing: {ex.Message}");
    }
}

c#
private Process _Client;
private Process _Server;
private List<Process> _ChildProcesses = new List<Process>();

public MainWindow()
{
    InitializeComponent();

    // Path to MonacoLuau folder
    string monacoLuauPath = System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "MonacoLuau");
    string nodeModulesPath = System.IO.Path.Combine(monacoLuauPath, "node_modules");

    // Check if node_modules exists
    if (Directory.Exists(nodeModulesPath))
    {
        string clientPath = System.IO.Path.Combine(monacoLuauPath, "Client");
        string serverPath = System.IO.Path.Combine(monacoLuauPath, "Server");

        _Client = StartProcess(clientPath, "run dev");
        _Server = StartProcess(serverPath, "run dev");

        // Track child processes of server and client
        _ChildProcesses.AddRange(GetChildProcesses(_Client));
        _ChildProcesses.AddRange(GetChildProcesses(_Server));
    }
    else
    {
        // Handle npm install logic
        RunNpmInstall(monacoLuauPath);
    }
}

c#
private Process _Client;
private Process _Server;
private List<Process> _ChildProcesses = new List<Process>();

public MainWindow()
{
    InitializeComponent();

    // Path to MonacoLuau folder
    string monacoLuauPath = System.IO.Path.Combine(AppDomain.CurrentDomain.BaseDirectory, "MonacoLuau");
    string nodeModulesPath = System.IO.Path.Combine(monacoLuauPath, "node_modules");

    // Check if node_modules exists
    if (Directory.Exists(nodeModulesPath))
    {
        string clientPath = System.IO.Path.Combine(monacoLuauPath, "Client");
        string serverPath = System.IO.Path.Combine(monacoLuauPath, "Server");

        _Client = StartProcess(clientPath, "run dev");
        _Server = StartProcess(serverPath, "run dev");

        // Track child processes of server and client
        _ChildProcesses.AddRange(GetChildProcesses(_Client));
        _ChildProcesses.AddRange(GetChildProcesses(_Server));
    }
    else
    {
        // Handle npm install logic
        RunNpmInstall(monacoLuauPath);
    }
}