Oh, and another thing I just thought of is something to record the first year physical milestones - smiling, rolling over, sitting up, first tooth, etc. Not necessarily a kit, though I'm sure it could be one, but something that could be used with other full kits as an addition? a card set, labels, stickers, word strips? something that a date could be 'written' on and used on a page to record when it happened easily. Or even maybe a full page with a list of common milestones with lines to record the dates on? Like I said I get lots of snaps with 'he did this just now or today' and I take screenshots to remind myself of when it happens for later.
My kids still ask me "when did I do that?" and I have to go pull out the old scrapbooks and look at the journaling on the pages to figure it out sometimes. With the twins back in the day I had two identical baby's first year calendars with a set of stickers for milestones. I had to fill out the calendar grids for the appropriate months once they were born. The top page of each month had the prompts of some kind for common things that would happen during that time period and there was also a set of stickers to just put on the date for easier recording. Gosh, now I'm going to have to go dig one of those out of the old memorabilia boxes and look at it
