"Days like years, and years like days" was one advice I got and how true is that. One moment we just got news that my dear wife was pregnant, and nine months later, we were at the hospital welcoming the birth of our firstborn. Days and weeks later, we were (and still are) fretting and pulling our hair about fixing her schedules and worrying about her well-being, and the next moment, she was already hitting 100 days old.
We get questions, like "eh boy ah, why 100 days? Last time all full month one." To be honest, we pondered upon whether holding a full month or 100-day celebration was better for us and Olivia. And ultimately, we chose to do the 100-day for a couple of reasons.