Holly and Ivy go together, very Christmas carol like. Rose stands out and does end with y and not 2 syllable or Christmassy. HollyRose and Lillian would be nice
Never heard of that before, but didn't realise Lily was in the Carol and was thinking of ChristmasLily and would match the y ending and 2 syllables. Christmas bell/Belle are pretty flowers but them no y or 2nd syllable