Science Reveals 12 Characteristics of the Happiest Couples

4. Fight at the beginning, then not a lot

Psychologists like Dr. Herb Goldberg suggest that our model for relationship is backwards–we tend to expect things to go smoothly at the beginning, and for problems (and conflicts) to arise later. In fact, Dr. Goldberg argues that couples should have “rough and ragged” beginnings where they work things out, and then look forward to a long and happy incline in the state of the relationship.

Research agrees: a Florida State study found that couples who are able to be openly angry in the beginning are happier long-term. According to lead researcher James McNulty, the “short-term discomfort of an angry but honest conversation” is healthy for the relationship over the long haul.

5. Are comprised of one first-born child and one last-born child

There’s an entire body of research on how your birth order impacts your life, including your relationships as well as professional success. One of the happiest pairings for couples? Someone who was the youngest child with someone who was the oldest.

Researchers hypothesize this may be because the relationship has one person who enjoys being taken care of, and one who’s used to taking care of others.

6. Know who does what when it comes to housework

According to a UCLA study, couples who agree to share chores at home are more likely to be happier in their relationships. An important caveat: couples who have clearly definedresponsibilities are far more likely to be satisfied.

In other words, when you know what to do and what’s expected with you, you tend to be happier both yourself and with your spouse. This might be a good thing to sit down and discuss in the new year, especially if you’re newly cohabitating.