The couple got engaged a week ago on her 36th birthday while the two were in London.

Jonas closed down a Tiffany store in New York City to buy an engagement ring.

A source says, "They are so happy."

A Jonas source tells PEOPLE, "His friends and family have never seen him like this, and they're all really excited for him. He's definitely very serious about her."

The news comes just two months after the pair began dating in May. Over the last several weeks, the 25-year-old singer and the "Quantico" star have been spotted on several dates, including a dinner date in New York City and a Beauty and the Beast Live in Concert show in Los Angeles.

Jonas and Chopra stayed in touch after hitting it off last year but things really heated up between the pair when they introduced each other to their families.