Hi Will !
I wouldn’t be concerned – at all – about capsizing an Edel 4 (nor any of the monohull this size, even intergral centerboard sailboats). Unless you are in HUGE breaker waves, taller than the boat itself (and you shouldn’t be there), it seems quite unlikely.
If it was, I wouldn’t take my kids aboard, and wouldn’t have bought this boat in the first place.
This boat is stable, will heel at something like 20° in rough weather.
Don’t launch the spinnaker unless you are confident doing so and you’ll be alright.
You still have to reef your sail according to the conditions, but it has more to do with sailing with less efforts and keeping the boat intact (not breaking things) than capsizing the boat.