For as much as having a new baby can be one of the happiest experiences of your life, there is another side to it. A side that is sleep deprived and navigating very unfamiliar territory. If you and your partner have been arguing more since bringing your baby home, you’re not alone: A new study got to the root of why parents of newborns fight more and—perhaps not surprisingly—it has a lot to do with the lack of zzzs we’re getting.

Researchers at The Ohio State University Wexner Medical Center recently examined blood samples from couples before and after arguments, and found those who were sleep deprived had higher levels of inflammation markers than normal.

In other words: Losing sleep primes you for an argument.

“Couples were more hostile to each other if they both had less than the recommended seven hours of sleep,” lead researcher Stephanie Wilson said in a media release.

Thankfully, Wilson said the study revealed some good news, too. “If at least one partner was well-rested, there was a protective effect,” she said. “They helped to neutralize the disagreement.”

It follows that a common bit of parenting advice may help new parents avoid arguing about inconsequential things: try sleeping in shifts. The Mayo Clinic recommends new parents split up overnight duties and work on a schedule that allows both partners to get some rest.

If both parents are equally exhausted, the UK’s National Childbirth Trust suggests asking a visiting friend or relative to babysit for a bit while mom and dad recharge. The NCT also recommends switching off phones when it’s time to sleep and prioritizing sleep over non-essential household chores. (Really, those dishes can wait.)

Getting the sleep we need is only one factor in preventing arguments. Being nice to each other matters, too.

In their book And Baby Makes Three: The Six-Step Plan for Preserving Marital Intimacy and Rekindling Romance After Baby Arrives, John Gottman and Julie Schwartz Gottman recommend parents broach potentially difficult discussions in a soft way. According to the Gottmans, we should use the word “I” instead of “you,” while accepting our own responsibility in the situation and stating what we need.

Kinder communication can not only prevent arguments from escalating, but may also make the quality of sleep better for both parents. A 2016 study published in Social Psychological and Personality Science found people who rated their partners as responsive to their needs had lower levels of anxiety and arousal, and in turn, better quality sleep.

And, at the end of the day, remember you won’t have a newborn forever. So, if you do have a fight about the baby wipes or who forgot to start the dishwasher, don’t take it personally.

After a good sleep, last night’s argument might seem kind of silly and you’ll be able to focus on what matters: That beautiful baby you created together.