This is a question that I happen to know the answer to, but I'll get to that. When you run across something like this as you compile your family cookbook, it's worth it to ask why. If something seems odd, it probably is. If you see a notation on a recipe card "from the kitchen of ___" and don't recognize the name, ask; the person may turn out to be your grandmother's bestie, or it might go deeper yet. If you find three different recipes for sugar cookies, all worn, and don't know why three, ask; there's probably a reason for that, too.*
My point is, don't just blindly accept the collection in front of you. Look at it like a historian – because that's what you are now. You are your family's food historian. Take in every date, every place name on every hastily-written recipe from the bank notepad or deposit slip, read the letters (if you're luck enough to find those in the collection), take it all in. Make notes, make scans, make copies and back them up. It's a ton of work, but someday, someone will thank you for it.
|On the left, my maternal grandmother's small recipe binder;|
on the right, my paternal grandmother's recipe box that won't close.
One represents a lifetime, one represents a collection that was started
in middle-age, when her children were already grown.
As for my mom's mom? When I was very small, they had a house fire. Whatever recipes she had from her mother were lost. The recipe collection I have from her now is no older than the early 1970s. Missing out on that older stuff stings, but knowing why it's gone helps. It's also a reminder to younger cooks to go and meet with your grandparents now, while you can. (By the time I married, only one of my grandparents was alive to see it, and she died later that year.) Or maybe you don't much cook yourself, but you have kids, or nieces and nephews, who are too young to appreciate the resource that their grandparents are – go, ask the questions, get the recipes, collect the stories. Before they're lost forever.
My book with more advice like this is available at Amazon.com. (If you buy a used copy, make sure it's the Updated Edition – the previous edition is out of date with regards to publishing.)
*In my family there are in fact, three Very Important Sugar Cookie recipes, and all of them are The Best. All of them were from someone's grandmother, and there's someone willing to die on that sweet hill over each of them.