You’re very welcome, sir!
Yup, once your Sunbursts begin breeding regularly, they will typically produce a new brood for you every month or so. And you can expect the brood size to increase over time as well, so it’s a good idea to implement any measures that may help boost the survival rate of the newborns in your refugium/natural nursery.
Cannibalism ordinarily isn’t a problem at all, so you shouldn’t have any problem whatsoever leaving the parents in with their offspring if need be. But there are indeed a number of other predators you should be aware of that can take a toll on the fry.
For example, aside from their parents, any fish with malls large enough to swallow the newborns are apt to do so. Likewise, decorative shrimp of all kinds — fire shrimp, cleaner shrimp, peppermint shrimp, etc. — will actively prey on seahorse fry and can rapidly decimate a brood. Snails are just fine but crabs of all kinds can pose a risk to the newborns after the fry pass through their pelagic phase and begin to orient to the substrate. Scarlet reef hermit crabs (Paguristes cadenati) and micro-hermit crabs that stay tiny and micro stars (miniature brittle starfish with a leg span no greater than perhaps a dime) are usually okay, but larger hermit crabs and serpent starfish may become opportunistic predators of baby seahorses.
Stinging animals such as hydroids (both the colonial stage and the hydromedusae jellyfish) and anemones will take a heavy toll on the newborns, so you’ll want to eliminate the Aiptasia rock anemones if possible.
Other than that, you just need to make sure that your filters and overflows don’t "eat" any of the newborns. Sunburst fry go through a pelagic or free-swimming planktonic stage and tend to cluster your the surface for the first several days of life, and these surface huggers are vulnerable to overflows and prone to getting filtered out, so beware of that as well.
Best of luck with your natural rearing system, Don! Here’s hoping some of the youngsters managed to thrive when left to their own resources amidst the abundant pod population in your system.