This is a really common question for us so I thought I would share our experience.
I took Ethany for her 3 year old check up with our Child Health Nurse. Living in a small community we knew the CHN and she was a lovely, welcoming person. Ethany did well with all of the instructions given, BUT she failed the eye test from a distance. We thought she must have been distracted as I had Xavier with me and he is a busy boy. We made another time to retest the following fortnight.
The next clinic day I arranged a friend to mind Xavier and took Ethany along. She failed yet again which resulted in our CHN recommended we see our GP to get a referral to an Opthamologist as she had failed quite badly :-( We were all quite upset and arranged to see a GP in a nearby town the following day. To make matters worse Russell came home with a horror story from a guy he works with whose little girl lost an an eye recently with a similar thing, had a 3yo check up, had a problem with vision test, had eye removed due to tumor. We were horrified at what might happen.
The GP we saw referred us on to a Pediatric Opthamologist in Perth. I rang and made an appointment then we waited.
Russell took Ethany along to the appointment where she had to have eye drops put in so the Dr could look inside her eye. This was not pleasant! His conclusion was that should would need glasses of +5.50 for both eyes and as her left eye was weak she would also need to wear a patch for about 3 hours per day. We were gutted by pleased that there was no tumor or other nasty.
I took Ethany to the optical disperser and let her pick out her own frames hoping this would give her some ownership over her glasses. Over the next week whilst waiting for the glasses to be made we prepared her for what was ahead. We made pirate patches and had a pirate party to help make her feel OK about the patch.
We collected the glasses from the optical dispenser and I made a big mistake! No one said to me her script is really strong wait till she is home to put them on or anything like that. We were in a shopping centre, I said you need to wear glasses now so pop them on and off we went. She was completely overwhelmed!! She had been looking at everything really small all her life. All of a sudden everything was really big. She complained like mad!
Since that moment we have good and bad times about glasses. She regularly says I hope at the next visit to the Dr they say I don't have to wear glasses anymore. Getting her to wear the patch is a struggle because she really can not see properly with it on so it frustrates her. She walks into things, can't read or look at picture books, can't draw, it really effects her.
After 18m seeing the same Dr we have requested a second opinion from a new Dr to see if there is anything we can do differently as the patching has not made any difference to the sight in the weak eye so far.

My darling daughter, her patch glasses and her Daddy.
This was taken a few days after she got her glasses. 'Percy' is now the right way up.
We had no idea that Ethany had any problems with her eyes. If it wasn't for our CHN visit we would still be clueless and probably wondering why she had really poor fine motor skills. I would urge everyone, please see your CHN for the 3yo check up. Even if you don't like your CHN or agree with anything they say your child deserves to see and hear and this 3yo screening can provide invaluable early intervention!!
Amber