Teen Travel to US

[Patchypups]

Can anyone give me advice please? … My 16 year old daughter is classed as an adult by the airlines, BA & AA. She is travelling to the US with my cousin and her family, different surnames. My daughter is meeting cousin and her family at the departure gate as they are flying in from Ireland.
I am preparing a permission to travel document and naming my cousin as her guardian for the week. Does this need to be notarised?

Any other helpful tips welcome! 😊

Are you sure you need anything? My DS flew alone to Idaho, changing in Dallas, when he was 15. I was going to send him as an unaccompanied minor, with a member of staff assisting him but he wanted to just go completely alone, and it was fine.

Which airline is it? DS was Delta iirc

Thank you, that’s good to know.
I’m not sure she does need anything at all at 16. It’s BA then connecting flight is American Airlines, she’s classed as an adult by the airlines.