that may seem familiar. >> iconic when william and diane new appeared there. >> reporter: 31 years ago dianna and prince charles coming down the steps to introduce their royal baby, prince william. >> may we see your son, your royal? >> all eyes on kathryn today like princess dianna 31 years ago. both new mothers in polka dot dresses, kathryn in blue, dianna in green. >> such a special time. i think any parent, i think, probably knows what this feeling feels like. >> reporter: this is not the first time she's become paired to princess dianna. take a good look at these pictures. notice anything similar. that's princess dianna in milan in 2005 and kate in 200 8, both in the same color pink. >> a lot of people ask is kate