What is a script that tells you in game if someone joined your group?

Like a little GUI that pops up on your screen when your at the groups homestore and says someone has joined your group.

As in if they are in your group?

game.Players.PlayerAdded:connect(function(plr)
if plr:IsInGroup(1337) then --Group ID Here

for k, p in pairs(game.Players:GetPlayers()) do
p.PlayerGui.JoinedGui.Frame.TextLabel.Text=plr.Name.."Has joined the group!"
p.PlayerGui.JoinedGui.Frame.Visible=true -- Change these to whatever the GUI looks like
wait(5)
p.PlayerGui.JoinedGui.Frame.Visible=false
end