Babys eye pupils diffrent sizes in dim light but normal in

Hello. This is Dr Geyik and I will be assisting you today.

Can I please ask your baby's age and if they have any medical conditions or take medications? 

Are you able to send a picture of the eyes in dim light here for assessment?

And are you aware of any recent trauma or injury, signs of pain, redness/bleeding/discharge from the eyes, fever, cough, vomiting, etc?

Is your baby growing and developing normally or have you noticed anything else unusual?

Finally, is there anyone else whose pupil size is different or was different as a baby?

In dim light or dark, the size of the pupils goes up to accommodate more light to see better. Both pupils normally increase in size equally.

In some babies, one pupil can be bigger or smaller than the other one and this doesn't always mean there is an underlying cause. It could be just a benign variation or rarely a genetic cause.

If they don't have any other symptoms, then I do not suspect anything sinister; but you should still see their GP for a routine assessment to ensure we are not missing anything else.

If you noticed that he has vision problems, signs of pain or headache, vomiting, developmental delay, etc?