My son is a Gemini and he can most definitely be a split personality, although not quite as bad as when he was a baby. When he was very young we were sure that his moods were dicated by the moon cycles - so unpredictable.
He can be very loving and affectionate, he is regularly away with the fairies, can be quite dizzy, but at the same time very protective of his siblings.
not two faced (I am one) But very indecisive. I am very very loyal to people, fwiw. But I do get bored easily. Wales - yy, I was deffo spilt personality when I was younger. Have levelled out with maturity. Creative, quick-witted, a born communicator, gossipy, fast-paced.