Size 70-80 Recommended for twins! I used these for my boy-girl twins. I really liked these because the necklines didn't stretch out easily, so I bought several extra, but I'm selling them to organize. The neckline opens wide with buttons, making them easy to put on and take off. These are cute long-sleeved shirts with lions and pandas. The neckline is buttoned, making them easy to put on and take off!