Hi PaulOS, if ye are both on the same network you won't need to get the unlocking code. If you want to request it just incase you can do this here. If they are using a basic phone at the moment they will need to get a micro SIM to use in the iPhone. If you need anything else let me know 🙂
No worries at all 🙂 If you need anything else you know where to find us 🙂