Seed difference?

[Starlight]

I'm not all up on tomato genetics, and was wondering this....

I'm saving seed now. I have lots of large tomatoes and some of those tomatoes are megablooms. I have the normal size ones th cultivar should be that were on the plant and from same cultivar different plant it made almost all megablooms.

When I save the seed, do I need to keep them separate and marked separate? I don't know if making megablooms is a trait that passed on to next generation or not.