Xamarin Portable Comments Stacklayout height problems Listview - xaml

Question

I am having trouble with height problems in Xamarin PCL with Listview. I want to create a comments section in a scrollable page. But i am struggling with the height of the comments. It just wont expand.
Row.Definition = Auto for the Grid:
<StackLayout Grid.Row="4" Padding="0,20,0,0">
<ListView ItemsSource="{Binding CommentsMVVM}" HasUnevenRows="True">
<ListView.ItemTemplate>
<DataTemplate>
<ViewCell>
<local:CommentsRow />
</ViewCell>
</DataTemplate>
</ListView.ItemTemplate>
</ListView>
</StackLayout>
In the CommentsRow template:
<Grid RowSpacing="0" ColumnSpacing="14" Padding="20" VerticalOptions="FillAndExpand">
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto" />
<ColumnDefinition Width="*" />
</Grid.ColumnDefinitions>
<Grid.RowDefinitions>
<RowDefinition Height="Auto" />
<RowDefinition Height="Auto" />
<RowDefinition Height="*" />
</Grid.RowDefinitions>
<Image Grid.Column="0" Grid.RowSpan="3" Source="{ Binding Image }" VerticalOptions="Start" />
<Label Grid.Column="1" Grid.Row="0" Text="{ Binding UserName }" VerticalOptions="EndAndExpand" TextColor="Blue" />
<Label Grid.Column="1" Grid.Row="1" Margin="0,4,0,0" Text="{ Binding CreatedAt }" TextColor="Grey" FontSize="13" />
<StackLayout Grid.Column="1" Grid.Row="2" Spacing="30" x:Name="StackLayoutMap" VerticalOptions="FillAndExpand" />
</Grid>
And at the C#:
public CommentsRow()
{
InitializeComponent();
var html_label = new HtmlFormattedLabel()
{
TextColor = Color.Black,
FontSize = Device.GetNamedSize(NamedSize.Small, typeof(Label)),
};
html_label.SetBinding(HtmlFormattedLabel.TextProperty, "Memo");
this.StackLayoutMap.Children.Add(html_label);
}
But the StackLayout comments text just wont expand automatically. What am i doing wrong?