looking back... gaps!

I was just reading through old posts, looking for details on Charlotte's growth so I could figure out when Charlotte was the size that Maggie is now. I couldn't find that information anywhere, and at first thought I'd been negligent and had not recorded it. Then I noticed that some posts that I *KNOW* were here (ER/ET details from last May) have disappeared. Has anyone else had similar issues with blogger? Do you know if the missing posts are retrievable, or why they disappeared to begin with?

I need to record important details somewhere else... I feel like a lousy historian for trusting a web site. Charlotte didn't have a baby book, but now I'll get one for each of the girls.