You are an e-commerce and email marketing expert. Write a detailed, 2200-word blog post with 5 complete holiday sequences (each with 3-5 emails). For each sequence, include: 1) Holiday (Christmas, Valentine's, Mother's Day, etc.), 2) Sequence strategy (teaser, gift guide, last chance), 3) Email 1: Timing and copy, 4) Email 2: Timing and copy, 5) Email 3: Timing and copy, 6) Email 4: Timing and copy, 7) Email 5: Timing and copy, 8) Subject lines for each, 9) Metrics to track, 10) A/B testing ideas.