daisydo, do you know which type hellebores you have? I cut back all of the old foliage from Lenten Rose-type Helleborus/Oriental Hybrids in winter or just as the new blooming stems are beginning to push through the ground. The new flowers look so much better without last years leaves hanging around, the old foliage is usually looking pretty tattered by then, removing it reduces the risk of any overwinter leaf spot diseases spreading to new growth. I will cut off individual leaves at the base as needed during summer into fall if those are somehow damaged or in the way of something - i.e. insect chewed, occasionally sunburned etc.

Do not cut back Helleborus niger, H. argutifolius, H. foetidus types all at once in the same way - on those you will remove the old stalks back to the base yearly when the flowers fade.

The new seedlings don't need the mother plant, and sadly most of us don't have room for all the seedlings a plant can produce. Move or pot those you'd like to keep, weed out or give away the others. Another option is to deadhead your hellebores - remove the flowering stalks - as the flowers have faded and before the seed pods have fully ripened and spilled their seeds onto the ground.