For a first camera for someone of those ages, I would tend to look for something not too expensive.
Something from $100 to $150.
You might consider either of these two Kodak cameras.
Kodak C533 - C643
About the only real difference is that one has 5 megapixels and the other has 6 megapixels.
Both take very good photos.
Here is a link to their specifications:
Does anyone have any suggestions for a good first-time camera for each of these ages? Thanks in advance!