FYI
most EU (and USA) carriers allow a small dog (not talking about a service or emotional support dog) to be carried on board as hand luggage into the cabin in an approved pet carrier/holdall and it must go under your seat in front of you
I have seen dogs on KLM LH AZ Condor aerolloyd IB Transavia and Delta
you can even take one out of LHR on LH and KLM (but you cannot bring a pet dog back into the UK so easily - check pet passport regs etc before you start booking)
you can also take dogs in the cabin to the Scilly Isles from NQY and LEQ on the skybus twin otter where they have a dog box put in place of a row of two seats - so you can sit opposite them
see here this Condor/Thomas Cook video of taking a chihuahua on board starts almost after Capt does his welcome - Our EU neighbours all love to take their little dogs and furbabies on holiday to the Med
and the making of the video see from 2m 15s
Condor website link
https://www.condor.com/eu/flight-pre...s-in-cabin.jsp
Coco and missy at NQY waiting to board our twin otter #delayed
not impressed so far
lol