The actress told Radio Times that "the only thing that's stressful [playing Rose Tyler] is walking down the street when schools are out. I don't know how David [Tennant] does it".
"Every child just thinks you're Rose and you don't want to spoil the illusion," continued Piper, who recently returned to the role at the end of Doctor Who's fourth season. "I really feel for David because that's his life - everywhere he goes is slightly chaotic."
"Sweet as they are, kids en masse are kind of frightening," she added.
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