It is partly true. Polaris is in fact a triple star system. The youngest of the three stars (Polaris Aa) is indeed younger than sharks at between 45 and 67My old. It is in tight orbit with Polaris Ab which is 500My old, and Polaris B which is 1.5By old and a little bit farther away. Here’s a pic from Hubble:
https://en.m.wikipedia.org/wiki/File:Polaris_alpha_ursae_minoris.jpg