Ran across, at least to me, an interesting situation today on an MSY-MEM flight. The GA announces pre-boarding in this sequence:

1. Those sitting exit row
2. Those needing special assistance or traveling with small children
3. Those seated in first class
4. Then, boarding by rows

Of course, this is the normal sequence. What I found odd was that probably conservatively, 33% of the plane boarded before the first class passengers. The reason for this it seemed that everyone traveling with a child under the age of 15 boarded with the second group. Some FC passengers attempted to board with group number 2 when it was obvious what was happening. The GA made them stand to the side until all of group 2 was boarded.

Which brings me to my question. How are those needing special assistance identified and how are “small children” defined?