Horror story involving child with disability

My name is Chris. I am so frustrated with a situation I find myself in, and the court system doesn't seem to have the best interest of a child at heart, and I would like to tell someone what is going on. This is going to be a long post, so be forewarned. Thank you for your time.

I recently started dating a girl Lindsey who has an adorable 4 year old child named Ellie, who has a rare disability called "congenital disorder of glycosylation". Basically when she was an infant, doctors told her that the particular class of this disability has only been documented in around a dozen cases and she would probably never walk, if she even survived through infancy. Lindsey was told later (after Ellie did start walking), that her mental capacity might not reach past that of a 2 year old. She is now four, and while she gets around fine, she has a very limited vocabulary. She can't really ask for what she wants (other than the occasional "up" to be picked up, or "more" for more food/drink) and she can get very frustrated because of this. She also is not potty trained, and so has to be in diapers. She sometimes can have mood swings, but most of the time is very sweet and loving.

Ellie's father lives in an apartment with his girlfriend, her twin 5 year-olds and an infant. Lindsey has custody of Ellie most of the time; her dad has Ellie on Monday and Thursday afternoons, and she stays at his place Monday nights and every other Thursday night. Up until just last week, he was only paying Lindsey $22(!) a week in child support. This was recently increased to $100 a week, which is somewhat more reasonable, considering $22 would pay for about one bag of diapers.

Lindsey picks up Ellie from her father's house, and she is like a completely different child. She is so angry, violent, she acts out towards Lindsey- hitting her, scratching her, trying to bite her, having screaming fits. Ellie is never like this when she sometimes has to stay at Lindsey's parents (Ellie's grandparents') house, if Lindsey has to work late. It's only after staying at her father's house. She also frequently has diaper rashes, scratches, and bruises upon returning from her dad's. One day Lindsey picked Ellie up and she had so much pee in her diaper it had leaked through and her pants were completely soaked... God only knows how long she was suffering in that pee soaked diaper/outfit.

Lindsey brings all these things up every time they see a judge in court in regards to custody (she is fighting for full custody). The judge's response? "Kids will be kids. They play, fight, fall down." Her drastic change in behavior cannot be "proven to be caused by time at her father's". Unfortunately due to her condition, Ellie cannot SAY what goes on in that apartment. She also has recently become extremely violent/upset when Lindsey changes her diaper, leading her to believe there could potentially be sexual abuse occurring (this, however, is only speculation).

In addition to her condition (possibly related to it), Ellie also suffers from very severe seizures. She sometimes turns almost blue in the face, and has a special shot with medication that she needs, as well as needing to go to the hospital. About a week ago, Ellie was at her dad's house and Lindsey was at work. Lindsey received a text message saying Ellie had a seizure, and that she could call him if she wanted. She immediately called him back, asked if Ellie was OK, and said she was coming to see her. The father said, "you can see her, but you're not taking her". Lindsey hung up, and headed over to see her daughter. When she showed up, the father opened the door a crack and said, "Don't worry, she's OK". Lindsey asked if he had called her neurologist to let him know Ellie had had a seizure, and should she increase her meds tonight, etc. The father replied he hadn't, and Lindsey said, "Ohhh! Of course not! Why would you call her doctor after she had a seizure!?!" The father's girlfriend (who apparently had been listening from behind the door) screamed, "You can't talk to him like that!" and slammed the door in Lindsey's face. Meanwhile, the whole time, Lindsey could hear Ellie crying in the background. Lindsey then knocked on the door again, and the girlfriend answered, shouting at her, "Who do you think you are talking to him like that?! This is his time with his daughter, you can't have her right now!" and then slammed the door again in her face.

Lindsey called the police, stating her concern for her daughter's safety/health/well-being. They arrived, went inside and said that, although upset, Ellie didn't seem to be in any danger. The police said that Lindsey could go see Ellie, but that she had to wait until 8:00pm to take her home. It was a little after 7:00pm at the time. Lindsey, as much as she wanted to check on her daughter, thought it would be more upsetting for Ellie to see her mom, want to go home with her, and then have Lindsey leave for 45 minutes until she was "allowed" to take her home. During this time, Lindsey had called her father (Ellie's grandfather), and he had come to see her. One of the neighbors arrived home at this point, and Lindsey's dad went to talk to him. His apartment shares a few walls with Ellie's father's apartment, and boy did he have some horror stories of things he has heard coming from that apartment. He hears constant fighting (between Ellie's father and his girlfriend, as well as the kids fighting, as well as the girlfriend screaming at the children), constant commotion, bangs, crashes, slaps. One day while Ellie was there, both the father and girlfriend came over to the neighbors apartment with the infant, and stayed there for 15-20 minutes of the other children being unsupervised. She has seen Ellie's father bloody from a fight with the girlfriend, he has seen the girlfriend pull her own hair out of her head, and then frantically call her parents saying that Ellie's dad had beaten her. There have been police visits required for domestic issues, and the girlfriend is clearly not emotionally/psychologically stable. The neighbor heard these words screamed from her mouth: "I hope your bitch of a daughter has a seizure and dies!"

Lindsey and Ellie's father have a court date on April 1st, and when given the court date, Lindsey laughed and said that date (April Fools) is appropriate, because she doesn't think anything will change in regards to custody. The neighbor agreed to give a written statement to the court, and hopefully he follows through. This whole situation has become mind-numblingly frustrating. I have only known Ellie since December (I met Lindsey in October, December is when we started dating), and I have clearly seen the difference in her behavior after she's spent time at her father's house vs. the rest of the week. It is as clear as night and day to me. I wish, I truly do, that Ellie could speak... that she could tell Lindsey, or me, or a judge what goes on in that looney bin of a house, but she cannot. All she can do is lash out, doing whatever she knows how to let Lindsey know it is not a safe situation at her dad's. Unfortunately the courts seem to turn a blind eye to all of this information, and it is just not fair. It is not fair for ANY child to be in an abusive/traumatic environment... but it just seems so much worse when the child can't even speak up about what occurs.

Anyway, if you've made it this far, please feel free to respond with any advice/recommendations/help you can, and again, thanks for listening to my rant.

-Chris