I had three.
1) Milka
I don't have pictures of her because I didn't have a phone/camera back then. I was about 11-12 years old.
Milka was born in the house. When Priscilla got broody, my mom wanted to take her eggs away. I remember that felt so violent for me at the time, lol, like "you're taking her babies away!". I insisted so much to let her have them - I even spent an afternoon (and planned to stay the whole night, lol!) next to Priscilla so that my mom wouldn't take her eggs, lol. That's when she said ok.
She had three babies, one of them was Milka. She lived a happy life alongside her family for a few years (can't remember how many), until she got paralyzed by Marek's disease. I remember taking her to the vet to rule out she didn't have a broken hip or something (there had been a storm and we thought that maybe something had fallen over her), but after some exams, we got the bad news.
I was told that she would never walk again and was offered to put her down. I was a child, and she was my pet, of course I said no. I took her back home and taught her to SLITHER! She had some mobility left so I encouraged her to use it so that she could move toward her feeder and waterer whenever she wanted to. For longer distances, I would simply carry her in my arms. For example, if the others were dustbathing, I would take her there and bathe her myself, lol.
I also designed a special swing (my dad built it) so that she could "stand up" and I would move her legs/feet as in some sort of physical therapy, lol.
My dad was building a wheelchair for her when she died overnight, about one month after her diagnosis.
Now I understand how questionable it is to keep a chicken alive in that condition, but I do not regret it. She wasn't in pain, and I was with her all day long, taking her to places and making sure she would eat and drink and spend time with her friends, etc. I like to think she didn't suffer that much.
2) Anton
Anton allegedly got Marek's disease, too (what a curse). He wasn't paralyzed, but one day he started walking like he was drunk, and fell over. I took her to a vet who said he had encephalitis, treated for that, and pretty much recovered, but.... he never walked like a normal chicken again.
He didn't fall over, but he had a weird walk. He couldn't roost, but he slept in a nest box. He couldn't jump to the coop's door (it is slightly apart from the floor), so I provided a ramp.
The problem was that Marek's left him immunocompromised, and he ended up getting wet pox. He died in my arms last year.
3) Bianca
Bianca survived pneumonia with pulmonary edema last year.
I took her to the vet in critical condition (they had to give her oxygen) and he even proposed to cull her. I committed to giving her a long treatment instead - one month of antibiotics every 12 hours, diuretics (to help her expel the fluids in her lungs) every 24 hours, and bronchodilators as needed.
She recovered from the infection and edema but ended up with tracheal stenosis and reduced lung capacity. Meaning, she breathes with noises and if she gets too nervous/excited or runs more than she should, she starts breathing with her beak open and making louder noises.
Sometimes, she needs to take bronchodilators because of that. But she mostly has a normal chicken life - with a few limitations, but she's learned to live with them. For example, she knows she can't run a lot so if the rest of the flock is running, she follows them at her own pace.
She also has reproductive issues. She has a tendency to lay soft-shelled eggs (if she lays at all - she mostly stopped laying after her illness). So, once in a while, she spends like 2 hours in the nest box or needs a warm butt bath. I must keep an eye on her in case of infections or prolapses (this happened once).
But I don't mind. She is my baby.
