I hope you’re not serious
there are no excuses for lazy character designs especially in this case.
Maybe this is sarcasm and I’m missing the point completely, in which case, sorry, but isn’t it because they are related?...
And they don’t look exactly alike… they look very very similar yes, as people as closely related as siblings and parent...
You guys its from the same art designer. I’m pretty sure there not related. that is just the artists style