Charlie Gard is born a "perfectly healthy" baby to parents Chris Gard, a postman, and Connie Yates, both from Bedfont, in west London.
Charlie is taken to hospital at eight weeks old after he begins losing weight and strength, with his parents describing how "none of us have been anywhere near home since".
He is diagnosed with a rare genetic condition at London's Great Ormond Street Hospital.
The mitochondrial DNA depletion syndrome causes progressive muscle weakness and brain damage. Charlie is only the 16th person in the world ever to have been diagnosed with the condition.
Both Mr Gard and Ms Yates were found to be carriers of a faulty gene, leading to their son's difficulties.
Charlie spends his first ever Christmas in hospital, with his parents posting touching pictures of the four-month-old dressed in an elf costume in his hospital bed.
Charlie's mother sets up a crowdfunding page after she finds an American doctor willing to offer her son a trial therapy.
Ms Yates says she had spoken to "doctors all over the world" and has endlessly researched a possible cure for Charlie's condition.
The treatment, called nucleoside, had success on children with a similar syndrome but has never been used to treat someone with Charlie's condition.
Charlie's parents reach their initial £1.2m fundraising target - a day before a High Court hearing into their son's case began.
The cash would pay for Charlie's travel by air ambulance to America as well cover the cost of the experimental treatment.
The fundraising appeal attracted the backing of celebrities, with model and heiress Tamara Ecclestone donating £10,000.
Reality TV stars Sam Faiers and Billi Mucklow also supported the cause, along with TV presenter Gaby Roslin and actress Linda Robson.
The target was later upped to £1.3m, with the sum met through donations by more than 83,000 people.
A High Court judge begins to consider whether Charlie's life support machines should be turned off in his best interests, or whether Mr Gard and Ms Yates should be allowed to take their son to America for experimental treatment.
During the course of the hearing, the court hears from the American doctor who had offered the trial therapy and the parents.
Proceedings were halted at one point after Ms Yates broke down while hearing medical evidence about her son's condition. Mr Gard sat in court with his son's toy monkey in the breast pocket of his suit.
He told the judge: "My son is the apple of my eye. I would do anything for him and I just want him to be given a chance, he deserves a chance."
Mr Gard and Ms Yates describe themselves as "devastated" after a High Court judge rules doctors at Great Ormond Street can turn off Charlie's life support machines against his parents' wishes.
Mr Gard screams out "No!" as the ruling is delivered. The couple say they cannot understand why the judge had not "at least given Charlie the chance of treatment".
Mr Justice Francis describes how he made the decision with the "heaviest of hearts" but with "complete conviction" it is in Charlie's best interests. He praises Mr Gard and Ms Yates for their "dignified" fight on their son's behalf.
Ms Yates reveals how she returned to Great Ormond Street after the ruling and told her son the couple were "sorry that we'd let him down". They vow to appeal the decision.
Ms Yates says the judge's decision means her parental rights have been "stripped away by strangers".
She tells the Daily Mail: "This isn't about us being selfish, keeping him alive because we can't bear to let him go. It is because if we did not fight for this chance, we will have to live with the 'what if' for ever."
Supporters gather opposite Downing Street to light candles and show their backing for Mr Gard and Ms Yates' campaign.
Their efforts include asking supporters to sign a petition and write letters to the Prime Minister, calling on her to help release Charlie from Great Ormond Street.
More than 110,000 sign the petition while thousands support Charlie's parents on social media accounts set up to highlight their fight.
Ms Yates and Mr Gard's local MP, Ruth Cadbury, speaks in the House of Commons and pleads with the Justice Secretary to intervene in the parents' legal fight.
Three judges at the Court of Appeal uphold the High Court's ruling that Charlie's life support treatment should end.
Mr Gard looks down and shook his head when the decision was announced, while family members broke down in court.
Lord Justice McFarlane praises Charlie's parents, saying: "My heart goes out to them."
Three Supreme Court justices dismiss a further challenge by Charlie's parents - meaning they have exhausted all of their legal avenues in the UK.
Ms Yates screams as the Supreme Court announces they have rejected the couple's bid for a full appeal.
Outside the court, Charlie's mother says: "How can they do this to us? They are lying. Why don't they tell the truth?"
Great Ormond Street are told to keep Charlie on life support for another 24 hours for the European Court of Human Rights (ECHR) to consider the case.
Judges at the ECHR rule that Charlie should be kept on life support until Monday 19 June at the earliest, giving his parents' lawyers time to submit detailed legal arguments.
After the ruling, the baby's family tweets: "Father's Day will be extra special this year as Chris will get to spend it with the apple of his eye Charlie!!"