Mother's Day viola

This was at my local Waitrose, no doubt intended for someone's mother. Mother's Day seems to be getting the same kind of treatment as Easter and Valentine's Day - not in the same league as Christmas, but in the next division below.

I've just been consulting the web about whether if should be Mother's Day or Mothers' Day or Mothers Day. The verdict is that Mother's Day has the edge over the other two, which I'm pleased about, as that's how I spelt it initially.