Today a second inquest opened into the death of toddler Jonnie Meek at Stafford Hospital in 2014.
A previous inquest which ruled that Jonnie died of natural causes was quashed after an independent doctor found that the milk he was given could have caused his death.
His parents John Meek and April Keeling have never stopped fighting for answers about what happened to their son. They both gave evidence at the inquest today, which was delayed from May because of the coronavirus crisis.
Jonnie lived with a range of medical issues including the genetic condition distal 18q- (De Grouchy Syndrome), asthma and various dietary intolerances.
Throughout his short life his parents and doctors tried various different liquid feeds in hopes of finding one that he could keep down and not vomit back up.
It was for one of these feed trials that April took him into Stafford Hospital on August 11, 2014.
Jonnie was administered the new solution at 1.30pm and stayed in the hospital for observations.
He became more agitated over the first 10 minutes and he continued to deteriorate, developing a rash, discolouration to his extremities and vomiting.
He began gagging and frothing at the mouth after about two hours and he was administered oxygen through a mask, but his condition did not improve and he died less than three hours after arriving at hospital.
An initial inquest concluded that Jonnie died of natural causes but his parents disputed that and it was eventually overruled, leading to a new inquest which began at Shirehall in Shrewsbury today.
Shropshire's coroner Mr John Ellery is hearing the inquest.
Jonnie's parents were the first witnesses to give their evidence to the inquest, both reading from statements they made soon after their son's death.
April said that because of his complex conditions, Jonnie was in and out of Stafford Hospital for large parts of his life. He was admitted several times with breathing problems and he was fed by a tube into his stomach at home as well as in hospital.
April said that she had "never seen" Jonnie react before in the way he did to the new feed. His extremities turned purple with a white rash and the skin around his mouth turned "dusky".
She said she was told that the purple colour was caused by Jonnie "working himself up".
Describing his final moments, April said: "I knew he had gone. I understand I was very distressed and calling Jonnie's name.
"I picked him up to hold him.
"I still feel really shocked at Jonnie's death. I still find it hard to sleep.
"I started to blame myself for his death.
"Jonnie had problems within 10 minutes of starting the new feed and they just got worse and worse.
"He was administered oxygen that day and he never had to have that at home. It had no effect."
Nurse Amanda Shenton, who helped care for Jonnie throughout the day, told the inquest she did not recall seeing him vomiting.
She said that the deterioration only took seconds and that she called for emergency help as soon as she realised he was seriously unwell.
Jonnie's family and the health authorities both have legal representatives at the inquest to ask questions of witnesses.
It is estimated that the inquest will last three days.