The devastated family of a 17-year-old boy who took his own life have issued a heartbreaking tribute remembering his “irreplaceable spark, kindness and wit”.

Robert Laurie Coates, from Marlow, was tragically found dead in woodland near Spinfield Lane in the town on March 8 this year.

The bright Sir William Borlase’s Grammar School pupil, who had a number of health issues and health anxiety, left a note on his iPad for his family, saying it was for this reason he was planning to take his own life.

In his note, he thanked his mum, dad, two brothers Matthew and Alex and his other family and friends for “giving me a great life” and told him he loved them and wished them the best for the future.

An inquest into Robert’s death was held at Beaconsfield Coroner’s Court on Wednesday.

Heartbreakingly, his family said in a statement that the teenager’s health issues could have been “successfully treated”.

They said: “His family, friends, teachers and doctors were totally shocked and saddened to hear of this tragedy. [He] could have gone on to have the wonderful future he deserved.”

The popular 17-year-old was a huge music fan, playing electric guitar and teaching himself how to play the drums and keyboard and represented his school in cross-country and hockey, as well as playing football and cricket for Marlow teams when he was younger.

He was a keen cyclist and was “nowhere happier than when surfing or body-boarding in the sea”.

Nearly 400 people attended a celebration if his life at Bisham Abbey, including over 250 young people and all of his teachers who walked to the church to be a part of the service – singing and sharing photographs.

The inquest this week heard how Robert had been seen at around 10am on March 8 sitting at the base of a tree in the woodland by dog walker Elizabeth Bird, who lived nearby.

She called over to him to see if he was okay but he had headphones on and did not appear to hear her.

That night, Ms Bird saw torchlight close to her home and called on her nephew Richard to check the area for burglars.

Upon investigation, Richard saw police in the area – who told him they were searching for a missing boy.

When he reported this back to his aunt, she recalled seeing a teenage boy in the woods earlier that day – and Richard then discovered Robert’s body and alerted police.

South Central Ambulance Service attended and he was sadly pronounced dead at 10.42pm. The teenager had died as a result of sodium nitrite toxicity.

Senior coroner Crispin Butler ruled that Robert’s death was suicide having “ingested a toxic substance”.

In tribute, Robert’s family said: “Robert was born into a loving and caring family and was much adored by his parents and older brothers. He worshipped his siblings, revelling in the boisterous nature of family life as the youngest of three boys.

“Robert was lucky enough to have good pals at school who replicated this sense of camaraderie and fun. He enjoyed getting up to low-level mischief with them and was always unfalteringly loyal.

“His friends and family prized his unique dry wit and Robert gained a lot of pleasure from making other people laugh.”

Robert’s head teacher at Borlase’s, Kay Mountfield, said: “The whole Borlase community are deeply saddened at the loss of Robert. He was so well-liked by everyone who knew him.”

She added that Robert was academically a “bright spark” who had won numerous national prizes and awards.

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