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Great advice here, I'm with casey on constant updating and that's a solid article from Herb. But for me you're asking the wrong question.  Sure updating content is great but you should really be testing it.  So test meta descriptions, H1's and other elements using a tool (there's this great keyword tool I believe it's called MOZ lol - lots of chat about that lately - they've really made some great changes.) But in the interests of openness I also use SEM Rush and GOOGLE  that's the best keyword tool out there.  Just get googling and see what sorts of articles are overtaking you and model them and make better versions. Having a young kid (congrats) means you're tired and creativity is really hard when you're tired and stressed - even for very creative people.  So model the articles of others and use the keyword suggestions and volumes as a guide. But always be testing and tweaking.  Add just a paragraph and revisit and change up some words and phrases and keep it fresh. Use the date in the Meta Description.  CTR in the SERPS is really important and If I see 2018 up there i'm going to click on it. Don't just add '2018' to everything though because google will catch you out. you actually need to add some contemporary stuff in there and it will revitalise and refresh the content. Also remember that there have been lots of changes at google lately. So your drop in traffic might be external ranking factors bumping other sites up because google can understand them better and is better able to get good user feedback from Chrome. Also be granular about it. Ask yourself of each article, "does this answer the question?" Is it up to date and is it correctly optimised using the keywords that are coming up in your research. The best SEO tool in the world is the 100 billion neurons sitting on your shoulders.  Use that tool first and foremost