Actually, all species of <i>Phelsuma</i> are cannibalistic with the exception of <i>Phelsuma standingi</i> (they will eat other <i>Phelsuma's</i>, but not their own offspring).
If the cage is big enough (well planted) and is VERY well sealed, you should be able to leave babies in with the parents. Baby <i>P. laticauda</i> are very tiny, however, and will often accept only fruit flies as a food item for the first several week of their life. I didn't have any luck getting them to eat pinhead crickets when I was working with them. Just something to think about ahead of time
Best of luck with the eggs!
JonK