ET spoke with the Suits star, who portrays Donna Paulsen, at the Good for a Laugh benefit at Largo at the Coronet in Los Angeles on Friday night, about reuniting with the Duchess of Sussex at her recent baby shower in New York City.
"It [was] just very exciting," Rafferty said about sharing that special moment with Markle.
Earlier this month, Markle made a trip to NYC to celebrate her and Prince Harry's baby-on-the-way. A royal source told ET that her shower at The Mark Hotel was co-hosted by Serena Williams and friend Genevieve Hillis. Williams' wedding planner, Jennifer Zabinski, reportedly coordinated the party. The shower, the source said, was an opportunity for Markle to catch up with friends she hadn't seen and to celebrate with those closest to her before returning to the U.K.
"I like away games," joked Harris, as Rafferty said her older children would make great baby sitters.
"She can totally hop on a private jet, bring her kids in," Harris noted. "Why not?"
"Maybe at her house, it's a little bigger," cracked Adams, adding that he and his wife, Troian Bellisario, haven't shared any parenting tips with his former onscreen wife.
"We've shared exactly zero tips with her, because I don't think Meghan needs any tips about anything," he said.
Friday's event, put on by Thomas Sadoski and Amanda Seyfried, benefited two organizations, War Child USA and INARA, for children whose lives have been devastated by war.
"What these causes are doing is incredible. They work from right inside the communities," Rafferty said. "So it's great to be able to shine a light on them and celebrate the work they're doing, and learn more about it."