“Going from being an ill teacher always struggling, I now embrace life.”

This is the mantra David Weston now lives by after a tumultuous 12 years.

The 37-year-old who works at Watford Grammar School for Boys, was given a second chance at life following a liver transplant after being diagnosed with rare condition ‘Primary Sclerosing Cholangitis’ (PSC) at the age of 26, in 2005.

He was under a lot of stress at the time after his mum was diagnosed with lung cancer and his skin started to turn yellow.

"I wasn’t doing much about it -I thought it was going to just go away. I remember going into school and a technician told me I looked really ill.

“I went to the GP in which I then was sent to one of the big London hospitals. It was there that I got diagnosed with PSC.”

Primary Sclerosing Cholangitis is a condition affecting the bile ducts and liver which can result in liver failure.

He said: “I didn’t tell my mum as she only had a couple of days left, the whole family was stressed out.”

“I was in and out of hospital having tests and unfortunately the night that my mum died I was rushed into hospital with an infection."

Doctors decided to treat David’s condition first before putting him on the organ donor list.

He said: “I went back to work in 2006 but for the three years that followed I was very unwell.

“In 2008 everything got worse. I was put straight on the transplant list for a new liver and thankfully the list for my blood type was moving fast.

“I was told I would probably get one within a few weeks and to always keep a bag packed in case they call me in.”

Things didn’t run as smoothly as David expected, months passed without a phone call and his condition deteriorated.

However one day, the phonecall came and he was left feeling a mixture of relief and nerves.

He said: “I was fully signed off work at the point I got a phone call telling me an ambulance was on the way,”

Despite suffering a few complications, the transplant was a success.

“I gradually started to get better and could finally go back to work. It was amazing to feel useful again and not like ‘just a patient’.

“The whole thing was totally life changing, when you’ve gone through something like that it makes you really want to just grab life.

“I just couldn’t believe how ill I’d been all those years, I even remember my last years of university feeling tired and itchy but never thought anything was wrong.

"I realised I had this incredible second chance at life which inspired me to get back into teaching and just go for it."

He became an advocate for LGBT students at his school and three months later, met his husband, Kevin Muscat.

Now, he is the chief executive of education charity ‘The Teacher Development Trust’ as well as the chairman of government expert group of teacher development.

And he is trying to encourage more people to sign up as organ donors.

He added: “The most important thing people don’t realise is you must speak to family and friends about donating, it’s the simplest thing to do but one of the most generous things.

“I urge anyone reading this to discuss donating with their family and friends.”