Tree Structure problem

Private Sub Button2_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Button2.Click
        makeTreeStruct()
    End Sub
 
    Public Enum Operation
        LessThan = 0
        GreaterThan = 1
    End Enum
 
    Public Class ParentNode
        Public value As Byte
        Public childern As New Dictionary(Of Integer, ParentNode)
 
        Public Sub New(ByVal value As Byte)
            Me.value = value
        End Sub
    End Class
 
    Public Sub makeTreeStruct()
        'Dim actualNumbers() As Byte = {5, 6, 1, 9, 7, 3, 8, 2, 4, 10}
 
        Dim actualNumberList As New List(Of Byte)
        actualNumberList.AddRange({5, 6, 1, 9, 7, 3, 8, 2, 4, 10})
        Dim ListofGTLT() As Byte = {1, 0, 1, 0, 0, 1, 0, 1, 1}
 
 
        Dim parentNodes As New Dictionary(Of Integer, ParentNode)
 
        Dim nodeIdCount As Byte = 0
 
 
        Dim tmpNumbersUsed As New List(Of Byte)
        Dim tmpId As Integer = 0
        Dim firstNumber As Byte = actualNumberList(0)
        Dim possibleNumbersToUse As New List(Of Byte)
        Dim numbersAlreadyUsed As New List(Of Byte)
 
        For currentLevel = 0 To UBound(ListofGTLT)
            If currentLevel = 0 Then
                'Generates Level 0 of all possible values in the first offset.
                possibleNumbersToUse = getPossibleNumbersForFirstByte(ListofGTLT(currentLevel), firstNumber, Nothing, 10)
                Dim parentNode As ParentNode
                'Generates parent nodes of all possible values in the first offset.
                For Each possibleNumber As Byte In possibleNumbersToUse
                    parentNode = New ParentNode(possibleNumber)
                    parentNodes.Add(tmpId, parentNode)
                    tmpId += 1
                Next
 
            Else
                possibleNumbersToUse.Clear()
                numbersAlreadyUsed.Clear()
 
                Dim pair As KeyValuePair(Of Integer, ParentNode)
                For Each pair In parentNodes
                    possibleNumbersToUse = getPossibleNumbersForNextByte(ListofGTLT(currentLevel), pair.Value, pair.Key, firstNumber, 10)
                    tmpId = 0
                    For Each possibleNumber As Byte In possibleNumbersToUse
                        If currentLevel = 1 Then
                            pair.Value.childern.Add(tmpId, New ParentNode(possibleNumber))
                        ElseIf currentLevel > 1 Then
                            Dim howMuchChildernIn As Long = currentLevel - 1
                            Dim lastChild As ParentNode
 
                            If pair.Value.childern.Count > 0 Then
                                lastChild = pair.Value.childern(tmpId)
                                While howMuchChildernIn > 0
                                    If lastChild.childern.Count > 0 Then
                                        lastChild = lastChild.childern(tmpId)
                                    End If
                                    howMuchChildernIn -= 1
                                End While
                                lastChild.childern.Add(tmpId, New ParentNode(possibleNumber))
                            End If
                        End If
                        tmpId += 1
                    Next
                Next
            End If
            tmpId = 0
        Next
 
    End Sub
 
 
    Public Function getPossibleNumbersForNextByte(ByVal op As Operation, ByVal aParent As ParentNode, ByVal index As Integer, ByVal firstNumber As Byte, ByVal totalSize As Long) As List(Of Byte)
        Dim numbersAlreadyUsed As New List(Of Byte)
        numbersAlreadyUsed.Add(firstNumber)
        numbersAlreadyUsed.Add(aParent.value)
 
        Dim lastOperationNumber As Byte = 0
 
        Dim lastChild As ParentNode
 
        While True
            If aParent.childern.Count > 0 Then
                lastChild = aParent.childern(index)
                numbersAlreadyUsed.Add(lastChild.value)
moreChildernCheck:
                If lastChild.childern.Count > 0 Then
                    lastChild = lastChild.childern(index)
                    numbersAlreadyUsed.Add(lastChild.value)
                    GoTo moreChildernCheck
                End If
 
                Exit While
            Else
                Exit While
            End If
        End While
 
        lastOperationNumber = numbersAlreadyUsed(numbersAlreadyUsed.Count - 1)
 
        Return getPossibleNumbersForFirstByte(op, lastOperationNumber, numbersAlreadyUsed, totalSize)
    End Function
 
    Public Function getPossibleNumbersForFirstByte(ByVal op As Operation, ByVal operationOf As Byte, ByVal numbersAlreadyUsed As List(Of Byte), ByVal totalSize As Long) As List(Of Byte)
        Dim possibleNumbers As New List(Of Byte)
        Dim tempNumber As Integer = -1
 
        While True
            If op = Operation.LessThan Then
                tempNumber = IIf(tempNumber = -1, operationOf - 1, tempNumber - 1)
            ElseIf op = Operation.GreaterThan Then
                tempNumber = IIf(tempNumber = -1, operationOf + 1, tempNumber + 1)
            End If
 
            If tempNumber < 1 OrElse tempNumber > totalSize Then
                Exit While
            End If
            If numbersAlreadyUsed Is Nothing OrElse numbersAlreadyUsed.Contains(tempNumber) = False Then
                possibleNumbers.Add(tempNumber)
            End If
        End While
        Return possibleNumbers
    End Function