Ive just become a member so that i could leave this message. I have read threads before regarding this subject and advice was mixed. So before i went to turkey june 2018 i rang jet 2 to ask them if i would have problems at the airport travelling with my twin babies 16 months having a different surname to me. Jet 2 said no so long as we all checked in together. I dont know why probably mothers instinct but i decided to take their birth certificates anyway. Good job i did because both turkish and british border controll questioned me as to who the babies belonged to. I dont know what would have happened if i couldnt have proved they were mine. I wanted to share this experience so that all you lovely mums are aware that the airports are getting stricter, and if you dont have full birth certificates as i dont for my older twins take tax credit/child benefit letters anything that shows you are the legal guardian xx