Steve and Leanne's son has been diagnosed with a devastating illness...
Soap fans have watched Oliver's health deteriorate over recent months, with him initially losing energy and sleeping a lot.
The news that their son has got mitochondrial disease will leave Leanne and Steve's world shattered, but what exactly is the illness?
And what is the prognosis for little Oliver?
What is mitochondrial disease?
Mitochondrial disease is a complex genetic condition that sufferers are born with, however the symptoms might not present themselves until later in life.
Mitochondria are found in nearly every cell in the body, and are responsible for producing the energy we need day-to-day.
The NHS compares these cells to power stations, making all the energy we need to function.
However, if our cells don't produce enough energy then parts of the body can't function.
A bit like in power stations, if there isn't enough energy there will be blackouts in parts of the country.
The parts of the body that are most affected are those that have the highest demands on the body, for example brain, muscles, liver, heart and kidneys.
What are the symptoms of mitochondrial disease?
Everyone with mitochondrial disease will show symptoms in different ways, depending on which mitochondria are working and not working within each cell.
Mitochondrial disease is considered a rare disease, and everyone showing slightly different symptoms makes it tricky to diagnose.
Oliver's tiredness, seizures and slower development in certain areas are all symptoms of this illness.
Other symptoms can include loss of vision and hearing, poor growth and breathing problems.
Can mitochondrial disease be treated?
Unfortunately there is currently no cure for mitochondrial disease at the moment.
Treatment for the illness is more focused on relieving symptoms that can develop, for example, treating seizures with medication.
Doctors can also use vitamins to help with energy levels and some people find a special diet can help relieve some symptoms.
Is Oliver Battersby going to die from mitochondrial disease?
Sadly mitochondrial disease is progressive, meaning it will only get worse over time.
The prognosis all depends on the individual, but the illness is sadly life-limiting and a substantial number of children with mitochondrial disease do not reach adulthood.
Coronation Street has been working closely with The Lily Foundation, a charity set up by mum Liz Curtis in 2007 in memory of her daughter, Lily, who died from the illness at just eight months old.
Coronation Street will temporarily air a reduced schedule of three episodes a week. Watch on Mondays, Wednesdays and Fridays at 7.30pm on ITV.
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