All this talk about Holly reminds me, I have a large Ilex verticilata in the back garden, it flowers every year, but only berried the first year I had it. Obviously it is a female that needs a male nearby, which I have not got. The native Hollies don't work, so if anyone knows how to get hold of an unwanted male, I think she would be interested.
Ilex verticillata does not look like a Holly, it is spineless, deciduous, but the beauty of this species is it retains its red, very Holly berries long after the leaves have disappeared. This makes them magical for flower arrangements as these berries stay fresh looking for a long time. But without a male, alas mine has bare branches.