The expectant women bumped into each other on the green carpet of the Safe Kids Day in Los Angeles, and immediately embraced in a warm hug.
Drew, who is due to give birth to her second daughter with art consultant husband Will Kopelman, looked absolutely radiant in a navy shirt, black trousers and black ballet pumps. The Charlie's Angels actress, 29, scooped her blonde locks into a ponytail and wore a slick of dark pink lipstick.
The pair seemed to have a lot to share as they chatted away, throwing back their heads in laughter. Pregnancy is certainly suiting Ciara too as the yummy mummy-to-be glowed in a white shirtdress and red flats.
She wore her hair loose in waves and opted for lip gloss and smokey eye makeup to complete her look. The Body Party singer, who is expecting her first child — a baby boy — with rapper fiancé Future, eagerly tweeted about the "educational playdate" before the event.
"Excited About Joining Safe Kids 2 Day!! Together We Can Protect Kids, Prevent Injuries, and Save Lives," she wrote alongside a photo of herself making peace signs with her fingers.
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Safe Kids Day aims to "raise funds and awareness for preventable childhood injuries" which are a number one killer in the US. The official website also offers tips to avoid common crib, car seat and household dangers.
Drew has previously opened up about becoming a mother for the second time. She and Will are already parents to 18-month-old daughter Olive and have made no secret of their desire to expand their family.
"We just wanted so badly for Olive to have a sibling," said Drew. "In some ways, it's really for her. So congratulations, Olive!"
"She's a sweet person, which is all I care about," the doting mother added, referring to her first child. "I am obsessed with nice. That's the most important thing."