My parents have a cocker.
As a puppy she suffered separation anxiety terribly and up until a year old would howl and defecate whenever left alone. It was very distressing for all. She grew out of it and is now the most laid back dog when left - happy to spend time alone in the house, caravan or happy to be left with strangers for the weekend, Really chilled about it.
She suffers with ear problems and has pretty much all her life. She has also had intermittent mouth problems. Spaniels ears (and mouths, often) need dedicated care to keep them in tip top condition.
She is very hairy and needs a good daily brush to keep on top of tangles.
Like almost every spaniel I know, she steals socks. This is adorable when she steals an old sock and infuriating when she takes the sock you want to wear. Being a spaniel she can get lost on a walk by following her nose so needed lots of work when young to keep her following her owner. She still couldn't be totally trusted if a pheasant walked by her.
She took constant and patient training. She would never respond well to being told off or corrected in anything but the calmest manner. She remains strong willed and stubborn so needs coercing into doing what you want. She loves food so coercion is rarely difficult.
She is affectionate and loving and you can bank on there being a waggy tail when she sees you.
In her younger years she was energetic and loved nothing more than being involved in whatever her family were doing. A real adventure dog.
She was left in a military dog kennel when young (the thinking was that she would be happier in there than home alone). I think the other dogs were too much for her and she learned to bite first, growl later. This habit has never left her. The dogs she likes, she loves. The ones she doesn't, she hates.
She also barks at the postman and always has, despite them trying to stop her.
She stinks when wet. The car never really loses the smell of wet cocker.
She is one of the best footballers I have ever seen and loves nothing more than a kick about. Her ball control is truly marvellous. True story.
In short, she is funny and friendly and loves her walks and has coped very well with a full life in which she can never be sure what the day will bring. She is barky, stinky and grumpy to other dogs and a bit stubborn.