It would be awesome for better communication. It would probably be best to have one Diary for each family so that everyone can keep the Diary for their children- but you could use one and different colored pens and have it travel!
We liked the bigger size for two reasons- one it is a little less expensive to produce. But more importantly, it gives you enough room to really share the details of the day plus add notes and questions and lists to keep you organized. You really need the real estate!
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