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:
I think it’s also worth mentioning that Polaris Aa, the youngest star in the triplet, is also the brightest by 3 orders of magnitude. Without Polaris Aa, we wouldn’t actually consider it as the North Star at all…so I think you are safe to continue using this as a fact.
Fun fact: the morning Star (first star we see in the morning) is in fact also the evening star (first Star we see in the evening). It's also not a star; it's just Venus.