Conscientious lovers are more caring.

If you planned a surprise party for your sweetie, but never got one back, that’s not a sign that they love you any less. They may simply be less conscientious. In a series of three experiments, researchers tested what makes romantic partners more or less caring.

In the first experiment, researchers invited college students to their lab to make a gift for their significant others, either the next day or several days later. Those who felt strong positive feelings for their partners were more likely to make a gift the next day, but no more likely several days later.

If they love their partners, then why did their thoughtfulness taper off? The second experiment showed that making a gift that required a week to prepare had nothing to do with love—only conscientiousness, or the tendency to have strong willpower. When the results weren’t immediate, will trumped love.

If your significant other is low on willpower (and short on gifts), don’t dismay. The third experiment showed that when subjects received a daily reminder of their love, they were more caring in the long-term. Maybe a kiss or an ‘I love you’ is all your honey needs.  

Nagging your partner to take out the trash is frustrating, and it’s easy to think, “You’d remember to, if you loved me.” Unfortunately, this common misconception builds animosity and conflict in relationships. And conflict isn’t pretty—it can lead to poor sleep, hypertension and even slower healing if you’re sick or injured.

Try communicating what you really need from your partner and help them come up with creative tricks to remember and prioritize what matters. Just don’t let your partner use this study as an excuse for forgetting your birthday!