How to merge cells in DataGridView using Powershell

Dear Powershell savants, I recently discovered that using WinForms with PowerShell is a great way to create small yet really useful GUIs. I'm currently working with DataGridView and am trying to get fancy with visual properties - specifically, I was wondering if there was a way to merge cells so that I could make 'sub-headers' reflecting which parent node from my tree is associated with selected children. If that doesn't make much sense, what I'm trying to accomplish is depicted in the following:

Is there a way to merge and center cells or at least a way to remove grid lines on certain cells to achieve the depicted salmon colored row effect?

This person and this other person asked similar questions although a PowerShell solution isn't readily translated.

Base code without tree functionality follows (adapted from technet post):

#The following is adapted from http://ift.tt/1G8Ejlb

function Get-ProcessInfo { 
    $array = New-Object System.Collections.ArrayList 
    $Script:procInfo = Get-Process | Select Id,Name,Path,Description | sort -Property Name 
    $array.AddRange($procInfo) 
    $dataGridView1.DataSource = $array 
    $form1.refresh() 
} 

#Generated Form Function 
function GenerateForm { 
######################################################################## 
# Code Generated By: SAPIEN Technologies PrimalForms (Community Edition) v1.0.8.0 
# Generated On: 2/24/2010 11:38 AM 
# Generated By: Ravikanth Chaganti (http://ift.tt/POdePY) 
######################################################################## 

#region Import the Assemblies 
[reflection.assembly]::loadwithpartialname("System.Windows.Forms") | Out-Null 
[reflection.assembly]::loadwithpartialname("System.Drawing") | Out-Null 
#endregion 

#region Generated Form Objects 
$form1 = New-Object System.Windows.Forms.Form 
$label1 = New-Object System.Windows.Forms.Label 
$button3 = New-Object System.Windows.Forms.Button 
$button2 = New-Object System.Windows.Forms.Button 
$button1 = New-Object System.Windows.Forms.Button 
$dataGridView1 = New-Object System.Windows.Forms.DataGridView
$InitialFormWindowState = New-Object System.Windows.Forms.FormWindowState 
#endregion Generated Form Objects 

#---------------------------------------------- 
#Generated Event Script Blocks 
#---------------------------------------------- 
#Provide Custom Code for events specified in PrimalForms. 
$button3_OnClick=  
{ 
    #$Form1.Close() 
    #$dataGridView1.SelectedRows | Foreach {$dataGridView1.Rows[$_.Index].DefaultCellStyle.BackColor = "Red"}
    #   $System_Windows_Forms_DataGridViewCellStyle_1.BackColor = 'White'
    #    $dataGridView1.DefaultCellStyle = $System_Windows_Forms_DataGridViewCellStyle_1

#Wipe Highlights without refreshing form 
for($i=0; $i -le $dataGridView1.RowCount-1; $i++) {$dataGridView1.Rows[$i].DefaultCellStyle.BackColor = "White"}


} 

$button1_OnClick=  
{ 
    #Get-ProcessInfo 
} 

$button2_OnClick=  
{ 

$dataGridView1.SelectedRows | Foreach {$dataGridView1.Rows[$_.Index].DefaultCellStyle.BackColor = "Red"}


#    $selectedRow = $dataGridView1.SelectedRows[0].Index
#    if (($procid=$Script:procInfo[$selectedRow].Id)) { 
        #Stop-Process -Id $procid -Confirm 
#        $dataGridView1.Rows.Item($selectedRow).DefaultCellStyle.BackColor = "Red"

    #} 
} 

$OnLoadForm_UpdateGrid= 
{ 
    Get-ProcessInfo 
} 

#---------------------------------------------- 
#region Generated Form Code 
$form1.Text = "Primal Form" 
$form1.Name = "form1" 
$form1.DataBindings.DefaultDataSourceUpdateMode = 0 
$System_Drawing_Size = New-Object System.Drawing.Size 
$System_Drawing_Size.Width = 517 
$System_Drawing_Size.Height = 414 
$form1.ClientSize = $System_Drawing_Size 

$label1.TabIndex = 4 
$System_Drawing_Size = New-Object System.Drawing.Size 
$System_Drawing_Size.Width = 155 
$System_Drawing_Size.Height = 23 
$label1.Size = $System_Drawing_Size 
$label1.Text = "Process Manager" 
$label1.Font = New-Object System.Drawing.Font("Microsoft Sans Serif",9.75,2,3,0) 
$label1.ForeColor = [System.Drawing.Color]::FromArgb(255,0,102,204) 

$System_Drawing_Point = New-Object System.Drawing.Point 
$System_Drawing_Point.X = 13 
$System_Drawing_Point.Y = 13 
$label1.Location = $System_Drawing_Point 
$label1.DataBindings.DefaultDataSourceUpdateMode = 0 
$label1.Name = "label1" 

$form1.Controls.Add($label1) 

$button3.TabIndex = 3 
$button3.Name = "button3" 
$System_Drawing_Size = New-Object System.Drawing.Size 
$System_Drawing_Size.Width = 75 
$System_Drawing_Size.Height = 23 
$button3.Size = $System_Drawing_Size 
$button3.UseVisualStyleBackColor = $True 

$button3.Text = "Clear Highlights" 

$System_Drawing_Point = New-Object System.Drawing.Point 
$System_Drawing_Point.X = 429 
$System_Drawing_Point.Y = 378 
$button3.Location = $System_Drawing_Point 
$button3.DataBindings.DefaultDataSourceUpdateMode = 0 
$button3.add_Click($button3_OnClick) 

$form1.Controls.Add($button3) 

$button2.TabIndex = 2 
$button2.Name = "button2" 
$System_Drawing_Size = New-Object System.Drawing.Size 
$System_Drawing_Size.Width = 75 
$System_Drawing_Size.Height = 23 
$button2.Size = $System_Drawing_Size 
$button2.UseVisualStyleBackColor = $True 

$button2.Text = "Highlight" 

$System_Drawing_Point = New-Object System.Drawing.Point 
$System_Drawing_Point.X = 230 
$System_Drawing_Point.Y = 378 
$button2.Location = $System_Drawing_Point 
$button2.DataBindings.DefaultDataSourceUpdateMode = 0 
$button2.add_Click($button2_OnClick) 

$form1.Controls.Add($button2) 

$button1.TabIndex = 1 
$button1.Name = "button1" 
$System_Drawing_Size = New-Object System.Drawing.Size 
$System_Drawing_Size.Width = 75 
$System_Drawing_Size.Height = 23 
$button1.Size = $System_Drawing_Size 
$button1.UseVisualStyleBackColor = $True 

$button1.Text = "Refresh" 

$System_Drawing_Point = New-Object System.Drawing.Point 
$System_Drawing_Point.X = 13 
$System_Drawing_Point.Y = 379 
$button1.Location = $System_Drawing_Point 
$button1.DataBindings.DefaultDataSourceUpdateMode = 0 
$button1.add_Click($button1_OnClick) 

$form1.Controls.Add($button1) 

$System_Drawing_Size = New-Object System.Drawing.Size 
$System_Drawing_Size.Width = 492 
$System_Drawing_Size.Height = 308 
$dataGridView1.Size = $System_Drawing_Size 
$dataGridView1.DataBindings.DefaultDataSourceUpdateMode = 0 
$dataGridView1.Name = "dataGridView1" 
$dataGridView1.DataMember = "" 
$dataGridView1.TabIndex = 0 
$System_Drawing_Point = New-Object System.Drawing.Point 
$System_Drawing_Point.X = 13 
$System_Drawing_Point.Y = 48 
$dataGridView1.Location = $System_Drawing_Point 

$form1.Controls.Add($dataGridView1) 

#endregion Generated Form Code 

#Save the initial state of the form 
$InitialFormWindowState = $form1.WindowState 

#Add Form event 
$form1.add_Load($OnLoadForm_UpdateGrid) 

#Show the Form 
$form1.ShowDialog()| Out-Null 

} #End Function 

#Call the Function 
GenerateForm

Is this possible?