So you finally got your baby into a somewhat predictable sleep schedule and then BAM! She’s back to waking up multiple times a night and you’re back to needing six cups of coffee to function. It just doesn’t seem fair, does it? But before you resign yourself to the life of a walking zombie, get the lowdown on those perfectly natural (yet super-frustrating) slumber changes and how to cope.

Wait, what is a sleep regression? Rebecca Kempton, MD and founder of Baby Sleep Pro, explains that “a sleep regression refers to a period of weeks (one to four) when your baby or child who had been sleeping well suddenly shows some blips in their sleep patterns, either at night or during naps.” The good news is that sleep regressions are temporary—so long as you don’t normalize them with your response (more on that later). The bad news? While the most common ages for regressions are three to five months, eight to ten months, 18 months and two years, they can basically happen at age—even into the double digits. (Talk about a rude awakening.)

How does that differ from a crappy night’s sleep? Although sleep regressions translate into a bad night’s slumber for your kid and for you (not to mention for siblings, neighbors, the dog and anyone within a two-mile radius), they’re more about a change in behavior over time. “We all have random nights of poor sleep but a sleep regression would not resolve on its own by the next night,” explains Julie Wright, MFT and co-founder of The Happy Sleeper.

What did I do to deserve this? Relax mama, this isn’t your fault. Depending on your child’s age, there are a lot of reasons why these relapses could be happening, including developmental surges, separation anxiety and changing sleep patterns. But all of these are perfectly natural and you can respond accordingly. Phew.

So what the heck can I do about it? It may be tempting to try anything to catch some z’s, but sticking to healthy habits is key—you don’t want to make a temporary regression permanent. That means making sure your baby’s room is sleep-ready and trying to nix any unhelpful associations or crutches, advises Dr. Kempton. “If you rock your baby to sleep, consider letting them learn the valuable skill of self-soothing. Or if your child was falling asleep easily and suddenly starts fighting bedtime, offer reassurance but then leave the room and let them fall asleep independently.” It won’t be easy, but then again, neither is getting through the day on two hours of shut-eye.

What about the dreaded four-month regression? So here’s where it gets tricky. When your four-month-old alters her habits, that’s not technically a sleep regression. “Four months is a permanent change in how babies’ brains are wired and when they switch to more adult-like sleep cycles,” explains Dr. Kempton. But that doesn’t mean that your four-month-old’s sleeping habits (or lack thereof) have to be the new normal. Make this the time to introduce sleep training, say experts.

Nothing is working. Trust your instincts. “If you feel that something medical might be the cause, it’s always best to get a doctor’s evaluation,” advises Wright.