"Tashi and lulu," the Shades of Blue star, 47, captioned the pic of her 9-year-old getting a piggyback ride from the former MLB player's 12-year-old.
The pic was posted a day after the "Ain't Your Mama" singer and the former Yankees player, 41, visited a nonprofit organization in the Dominican Republic, where they donated backpacks and school supplies.
Lopez was in the Caribbean for a joint concert with ex-husband Marc Anthony — her first ever show in the Dominican Republic — on Saturday, April 15, and the new couple later visited a local nightclub where they were spotted dancing with Anthony, whose divorce from Lopez was finalized in 2014.
The show of family togetherness comes a little over a month after Us Weekly broke the news that the Grammy nominee and A-Rod were dating. As previously reported, the pair were quietly seeing each other for a few weeks before their relationship made headlines in early March.
Since then, the lovebirds — who first met back in May 2005 — have taken multiple trips together including getaways to Miami, the Bahamas and California.
An insider previously told Us that Lopez and Rodriquez have clicked because "they are in the same place in their lives; they both have kids around the same age."
The former American Idol judge shares twins Emme and Max with Anthony, while Rodriguez has two daughters, Natasha and Ella, 8, with his ex-wife Cynthia Scurtis.
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