See Every Photo from Kate Middleton and Meghan Markle's Commonwealth Day Reunion
Kate and Meghan greeted each other with a friendly kiss on the cheek.
The two couples chatted as the rest of the royal family made their way into the service.
Harry and Meghan chat with Prince Charles ahead of the service.
Meghan and Harry spoke with officials as they left the servce, which was also attended by the Queen, Prince Charles and Camilla, Duchess of Cornwall.
Meghan and Harry, who are expecting their first child in late April, greeted young children outside Westminster Abbey.
Kate and William also chatted with the children, who gave the royal mom flowers, upon their exit.
William and Kate greet church officials.
Meghan wore a cream coat with a matching Victoria Beckham print dress and pillbox hat.
Kate arrives in one of her favorite Catherine Walker coat dresses, which she also wore in 2014 during her tour Down Under with Prince William and a then 9 month old Prince George.