I get the question “Do you think I need to sleep train again?” a lot. My advice is not to think of sleep training as a quick-one-time-fix. It really begins to boil down to a parenting method related to sleep. More often than not, teething, traveling, illness, developmental milestones or simply the knowledge your baby gains (eventually) that crying gets him what he wants can throw a wrench in even the most peaceful sleepers. Once my first son was “sleep trained”, we had to revisit over and over because of his spirited personality. Then, we’d have a string of great times and then fall back, again. It was sooo frustrating! But, necessary.
So, my advice is that you need to tend to your baby when she is sick, teething, etc. but once she is well again, you may need to go back to your sleep training method of choice to get things back on track. Many times it’s more about setting limits and deciding what you will and won’t do all night long, and how much sleep you decide is too much for your child to lose.