How to make each form it's own thread and able to update? - vb.net

Question

I am have three(4 counting the main one) threads in my application(chat app) and I want to put each form into it's own thread(one thread does not need a form so it is irrelevant). The 2 forms I am working with are clocks with a local digital font included. The problem is that threadb will start and run, but threadc will remain as the text LABEL1 and not change at all to: MM/dd/yyyy hh:mm:ss tt. I am wondering how to get these threads to work together.
Here is the thread code(creating at beginning of porgram, this is from sub official_start):
threadb = New Threading.Thread(AddressOf form3threadsub)
threadc = New Threading.Thread(AddressOf form4threadsub)
threadb.IsBackground = False
threadc.IsBackground = False
threadb.Start()
threadc.Start()
Here is the code for the thread subs:
Private Sub form3threadsub()
Dim first As Boolean = False
Do
System.Threading.Thread.Sleep(100)
If first = False Then
form3.ShowDialog()
first = True
End If
form3.Label1.Text = DateTime.UtcNow.ToString("MM/dd/yyyy hh:mm:ss tt")
form3.Update()
Loop
End Sub
Private Sub form4threadsub()
Dim first As Boolean = False
Do
System.Threading.Thread.Sleep(100)
If first = False Then
Form4.ShowDialog()
first = True
End If
Form4.Label1.Text = DateTime.Now.ToString("MM/dd/yyyy hh:mm:ss tt")
Form4.Update()
Loop
End Sub
Here is the button2 click:
Dim clicked As Boolean = True
Private Sub Button2_Click(sender As Object, e As EventArgs) Handles Button2.Click
If clicked Then
threadb.Suspend()'obsolete
threadc.Suspend()'obsolete
Button2.Text = "Resume Clocks"
clicked = False
Else
threadb.Resume()'obsolete
threadc.Resume()'obsolete
Button2.Text = "Pause Clocks"
clicked = True
End If
End Sub

Answer 1

I think I found my working solution. I took the extra forms out and replaced them with labels on the main form. Each label is it's own thread and updates accordingly.