Connor Sparrowhawk died while under the care of an Oxfordshire NHS unit.
The 18-year-old had suffered an epileptic seizure at Slade House in Headington in 2013.
Southern Health NHS Foundation Trust was fined £2 million earlier this year for failures that resulted in the deaths of the teenager and another patient.
As the government pledges new measures to improve hospital care for people with learning disabilities, Connor's mother Dr Sara Ryan tells Sky News why she believes the proposals are too little, too late:
Connor's nickname was laughing boy, or LB for short. He had a brilliant sense of humour.
He would laugh without making a sound, his shoulders going up and down.
We would compare him to Muttley from Wacky Races, with his infectious laugh and massive grin on his face.
I was at work when I got the phone call to say he had been found unconscious in the bath. He was already on his way to hospital in an ambulance.
It was only in the cab on the way to the hospital that I started to panic.
"Oh my god," I thought. "What is going to happen?"
When I got to the hospital, the consultant came out straight away and told me that Connor had died. It was completely devastating.
I kept thinking about how he had been due to go on an Oxford bus tour that morning. There was a school prom the next day that he was due to attend. It should have been so ordinary.
It rips your world into pieces. And he died in a way that was so preventable.
Since Connor's death, it's almost been a full-time job getting accountability for what happened.
He had a strong sense of justice and I knew he would have expected us to fight for it.
Southern Health Trust was fined an enormous amount of money.
I had been called a toxic mother and all sort of other awful things while the trust was investigated. When the judge called out their awfulness for what it was, it brought some comfort.
We still have other cases to fight for but we did Connor proud.
Lots of other families have been in touch. With most NHS scandals, it's the families that end up campaigning.
Connor should have been looked after and, when he died, we should have been supported.
We shouldn't have had to embark on such a tough journey.
While there are some positive steps in the government's response to the learning disability mortality review (LeDeR), and clear recognition that it is unacceptable that people are dying premature deaths, it smacks to me of too little, too late.
It is vague, underwhelming and includes some heart-sink deadlines which extend into the never never. The pace of change is truly glacial while people continue to die.
We have report after report, inquiry after inquiry, countless "prevention of future deaths" reports from inquests and a substantial body of research evidence to draw on.
The problem is wider than training and involves discounting people.
Connor, and others, died because they were not seen as fully human; their diagnoses erased any consideration of their health.
In 2013, a confidential inquiry into the premature deaths of learning disabled people recommended the setting up of a national mortality review board.
The government at the time refused to do this saying it was too expensive and, instead commissioned the LeDeR work.
Five years later, with mortality rates worsening, it's clear urgent and effective action is essential.
Piecemeal fudging and yet another consultation is simply not good enough.