Dane Cook, 45, is dating a 19-year-old singer — how weird is that?

Dane Cook, 45, says his 19-year-old girlfriend is a “gift” and he doesn’t care who knows it.

For the past year, the comedian has been living a quiet life with singer Kelsi Taylor, Instagramming cute shots of the pair on Christmas, prepping Thanksgiving dinner, and going to the movies.

On Friday, Cook named Taylor in a post that read, “Be a warrior, not a worrier.” He wrote, “The next few months are work hard/play hard ones. I’m grateful to my friends and fans who continue to support my artistic endeavors. I can’t get to where I’m going without this foundation of support. My sister & right arm @_courtneycook_ – talented & helpful x10000. My gf @itskelsitaylor who quite simply is a gift.”

A week ago, he shared an image of him and Taylor on date night after visiting an escape room, writing, “On a cold night we sipped hot beverages & escaped Dracula’s tomb. #escaperoomexperts #relationshipgoals.”

And in August, Cook captioned a selfie of the couple poolside, writing, “Breakfast for dinner with my best friend.”

However, fans and tabloids are just taking notice of the pairing — and many are confused by the couple’s age gap.

It’s not unusual for Hollywood couples to have mismatched ages: There’s a 19-year gap between Amber Tamblyn and David Cross, 12 years between Jay Z and Beyonce, 11 years between Blake Lively and Ryan Reynolds, and 17 years between George and Amal Clooney. Other notable May-December romances are the 25-year difference between French president Emmanual Macron and wife Brigitte Trogneux and the 24 years between Donald and Melania Trump.

The research on these types of relationships is grim: A study by Emory University found that couples with a 5-year difference are 18 percent likelier to split, couples with a 10-year divide have a 39 percent failure rate, and those who differ by 20 years have a 95 percent of splitting.

Another study published in the Journal of Population Economics analyzed levels of marital satisfaction between couples with large age gaps (in which either the man or the woman was older). Findings revealed that people with younger partners are happier at first but after 6 to 10 years of marriage, satisfaction starts to decline, compared to couples that are closer in age. No one knows why but one guess is that couples with an age gap are less resilient to weathering marital problems.

There may be a cerebral explanation for why it’s difficult to have long-lasting love with someone older: The human brain doesn’t reach full maturity until age 25.

Neuroscientist Sandra Aamodt, told NPR in 2011, “So the changes that happen between 18 and 25 are a continuation of the process that starts around puberty, and 18-year-olds are about halfway through that process. Their prefrontal cortex is not yet fully developed. That’s the part of the brain that helps you to inhibit impulses and to plan and organize your behavior to reach a goal.”

Aamodt added that before age 25, the brain’s reward center has not reached “adult level,” drawing young people to uncertain situations in the hopes of personal gain.

It’s possible that Cook and Taylor will beat the odds and no one can argue with genuine chemistry between two consenting grown-ups. But according to Los Angeles based psychoanalyst Bethany Marshall, PhD., these types of couples should stay realistic. “Developmentally, a 19-year-old woman is still consolidating her identity and may not be ready to make a life choice such as a serious relationship,” she tells Yahoo Lifestyle.

Some older men are drawn to younger women who aren’t yet autonomous or may not have the relationship expectations of a more experienced woman, she says. Others may seek out younger women believing they’re more pliable to influence. For a younger woman, an older man may offer a novel or exciting experience or the opportunity to learn from someone more seasoned.

The obstacle for couples who care for each other is to stay aware of the other’s life path. “A 19-year-old will be a totally different person in ten years,” says Marshall. “The same might not be true for someone who is 45.”

Read more from Yahoo Lifestyle:

• Is love at first sight real? Meghan Trainor thinks so — but what about relationship experts?

• Kim and Kanye’s baby name ‘Chicago’ is unprecedented, says name expert

• Why does a woman dating a shorter man make people so uncomfortable?

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