We use every to talk about three or more. (Instead of ‘every two’ we say both).
We say every when we are thinking of people or things together, in a group. (Every is closer to all.)
- We want each child to develop in his or her own way.
We want every child to be happy.
Each person in turn went to see the doctor.
He gave every patient the same medicine.
The difference is not always very great, and often both words are possible.
You look more beautiful each/every time I see you.