Gwen Stefani joined friends for a walk on London's Primrose Hill, and afterward the group, including her youngest son Zuma, grabbed dinner at the Princess of Wales pub. Today, Gwen was back out in her North London neighborhood for a walk with Kingston. Gwen's stay in England with husband Gavin Rossdale and their children has been dotted by many reunions with their pals. Gwen Stefani and Angelina Jolie organized a playdate for their young ones earlier this week, giving Kingston and Zuma a chance to paint and play with Shiloh, Knox, Zahara, and Vivienne. The Jolie-Pitts and Stefani-Rossdales have been friends for a long time, with Kingston and Shiloh coincidentally being born just one day apart! Twins Vivienne and Knox are also close in age to Zuma, giving the kids a great deal in common.