Being wrong is not something to be happy about.

Hang on, if Person A sits on an asteroid for 50 years and person B flies around at 0.5c and comes back when person A reaches 60 years, Person B will be a lot younger. Because if Person B flew around for 60 years at 0.5c, Person A may have already died of old age.

In order for person B to arrive to person A when person A is 60, Person B would need to fly for much less than 60 years, therefore he will younger looking because he is younger!

Here's a good brain teaser.... If we had 2 people, both 10 years old and one flew away at 0.99c, how long would he need to flying (from his perspective) to get back to person A when person A is 60 years old? How long at 1.0c?