Started off a couple of days ago when ticking him.First he was lifting his leg up whilst I was tickling him now it's progressed to a full on laying on his side,sometimes his back for his belly rubbing,whilst purring away.Little Theo watching on curiously.Is this normal behaviour.They are also following me around as if they see me has lead Guineapig and when I sit on the floor to spend quality time with them they run around me in circles cooing and purring.