16 year old going to Spain with friend

[rottweilersrock]

My 16 year old son has been invited to go to Spain with his friend and parents (who are Spanish). He has already booked his own flight out there, although he will be travelling with the family.
When he returns, he will be coming back with just his friends mum. She is going to book the tickets for this return journey.
As he is only 16 and will not be travelling with parents, does he need some kind of letter of permission from us to travel? I’m struggling to find a definitive answer for this online.
He is flying with Ryanair on the way out, and presumably the same for the return journey.
If anyone has any advice I’d be very grateful

Hopeful bump for the evening crowd!

It's definitely worth doing. We took my daughters friend on holiday with us a few years ago and on the way back at Calais were asked if we had any documentation showing it was ok for her to be with us. We didn't (all I had were texts between me and her mum) In the end they asked her if she was being kidnapped, she said no, and we were free to go! Since then we've always had a letter. There are templates online. Also useful if, in the case of an emergency, your son's friends parents might have to consent to medical stuff.

get a template on line.
We have a place in Spian so often take the Dc friends and I always have a letter from the parents for under 18's and I have been asked for it

My son flew back from Germany on his own last year when he was 17. I couldn’t find a definitive answer on whether he needed a letter or not so just wrote one myself. Thought it better to be safe than sorry. Put my full name and passport number on it. He didn’t need it however.

No - once they are 16 the airline literally don’t care. I flew out with dd1 and her friends as she was 15 and they were all 16 - easyJet checked them all in without batting an eyelid the fact the other teens were 16 enabled my 15 year old to travel with them. I was poised to step in as the adult but nope wasn’t needed.

Hi, travel agent here,

Your son will NOT need a permission letter from yourselves to fly.

When you book with Ryanair adults are 16+

Your son will be okay OP! Double check which airline it is coming home, majority of airlines class adults as 16+ and will not require parents permission!

The airline never asked us but the Passport control staff did in both Spain and Portugal

Will that still count if his friends mum is making the return booking?

Thanks everyone for your comments. Is there a particular template that is suitable?
Having spoken with his friends dad, he seemed to think it might need stamping by the police or someone to return from Spain. I’d hate for there to be any problem for my son on his first trip abroad without us