Mary-Kate Olsen shared a sweet kiss with boyfriend Olivier Sarkozy in New York City Credit: Turgeon-Steffman / Splash News

Mary-Kate Olsen and Olivier Sarkozy are taking their romance to the streets. The couple, who've been known to pack on the PDA courtside at New York Knicks games, were spotted sharing a sweet smooch on a sidewalk in New York City on Thursday, Dec. 12.

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Olsen, 27, had to tilt her head up to make contact with her much taller, much older beau, 44. She wore black skinny jeans and carried a black purse; he dressed up in a blue suit and had his hands full with papers and mail.

Together since May 2012, the former Full House star and her banker boyfriend live together in a $6.25 million townhouse in New York. Engagement rumors are rampant, but as a source reveals in the new issue of Us Weekly, Olsen would rather have a baby than a wedding.

"She'd like to get pregnant but isn't so sure about marriage," an insider told Us of the twin.

Sarkozy, for his part, is already dad to kids Julien, 12, and Margo, 10, with ex-wife Charlotte. "Mary-Kate has made him a better father," the source said. "She remembers all the kids' special events. She thinks he's a great dad."