Telling sign Jake Gyllenhaal and girlfriend Jeanne Cadieu are getting serious (report)

Things are heating up between Jake Gyllenhaal and his girlfriend, Jeanne Cadieu.

The "Nightcrawler" actor was first casually linked to the French model back in December, but recent sightings and new details point to the couple becoming more serious.

Page Six reports that Gyllenhaal, 38, has introduced Cadieu, 23, to his family recently, and the couple recently went on a romantic getaway to Martha's Vineyard off the coast of Cape Cod.

SEE ALSO: Maggie Gyllenhaal opens up about 'valuable' relationship with brother Jake

Cadieu has also been spotted at a slew of previews for "Sea Wall/A Life," the limited run Broadway play that Gyllenhaal stars in alongside British actor Tom Sturridge. The pair also both appear in the "Inside Out" photo exhibition, which features portraits of a large group of famous faces, including Gyllenhaal and Cadieu, on the walls outside of the Hudson Theatre, which is home to "Sea Wall/A Life."

See photos of Jeanne Cadieu:

The rumored couple has been spotted numerous times over the past several months, including a January dinner date at a New York City Sweetgreen where onlookers said that Gyllenhaal looked "super smiley" and "so happy." She also attended the June premiere of her boyfriend's latest movie, "Spider-Man: Far From Home," though they didn't walk the red carpet together.

Ahead of the limited Broadway run for "Sea Wall/A Life," Gyllenhaal opened up to AOL about his love for theater and the different way in which it allows him to connect with audiences.

"I’ve learned how much love there is when people decide to come to the theater and that the love of the theater is a very particular kind of thing. It's the love for that live experience," Gyllenhaal told us back in June. "It’s a commitment, and I consider it to be an honor every night when I get out there to perform for a large group of people who have gathered and paid for that specific thing. It’s something you don’t get when you do television or film. You never really feel that feeling, and I think that anticipation moved us into realizing how much we appreciate and love the audience that comes together."

SEE ALSO: Jake Gyllenhaal: 'I hope to be a father one day'

While he's certainly receiving support for his latest acting project from his girlfriend, Gyllenhaal has also been getting input from his sister, fellow actor Maggie Gyllenhaal. During a separate interview with AOL, Maggie explained that their brother-sister relationship is extra "valuable" because they can give each other genuine feedback on their various artistic works.

"I know how much my reaction to his work affects him, and that’s such a beautiful thing to go in curious and loving and warm to watching someone you love do their work," she explained. "I feel that way about just a few people, and he’s one of them."

See photos of Jake Gyllenhaal from earlier in his career: