The most common cause of lazy eye is a squint. It is a condition in which both the eyes are not aligned together, meaning one eye will look straight while the other will look either up, down or to the side.
In such cases, both the eyes may take completely different images and send them to the brain. To avoid doubling of the images, the brain blocks the signals from the weaker eye, hence relying just on one eye to see. 
The cause of abnormality in one eye is the disruption of the nerves behind the eyes which help in sending signals to the brain. There are multiple causes of nerves disruption. The common causes are:
Children under age seven are at higher risk of developing lazy eye due to:
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Lazy eye is best to be treated at an early stage. If the condition continues for long, it may cause permanent vision loss or blindness of the weaker eye. 
Lazy eye can be diagnosed best at home. If you see any of the aforementioned symptoms in your child, test their eye by the following methods:
Other tests include:
Treatment of lazy eye should start as early as possible. The methods include:
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1. Can you fix a lazy eye?
Ans. Though fixing a lazy eye at childhood is considered beneficial, it can be fixed at any age due to the advancement in neuroscience. The treatment method during childhood includes prescribed glasses, eye patching, surgery and some therapies such as eye exercises.
2. Can you fix a lazy eye in adults?
Ans. Treatment of lazy eye in adults is not offered usually. This is because there's a particular age up to which the treatment methods work. Patching therapy is considered useful until the age of 12 while surgery is demonstrated good up to the age of 17.
Lazy eye, also termed as amblyopia is a vision development disorder mainly developed during childhood. In this disorder, the vision of one of the eyes does not develop fully as the brain focuses only on the normal eye, ignoring the one that doesn't function well or is a 'lazy' eye.
Poor vision in one eye takes place when there's a breakdown of nerve cells in that particular area. The nerves are unable to mature properly, hence making the sight unrecognisable for the brain. Amblyopia usually develops between birth until the age of seven. It is prevalent in 1 out of every 50 children. Take a look at its details.
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