National Siblings Day: Blake Lively, Justin Theroux and More Stars With Super-Sexy Brothers and Sisters!

See which Hollywood celebs have super-attractive family members

All good things come in pairs! And for these Hollywood celebs it's a great set of genes.

Justin Theroux and Blake Lively are only a couple of celebs that have beyond sexy siblings. Little did we know a handful of stars are related to some seriously super-attractive brothers and sisters (lucky us!).

We guess the saying is true: Good looks do run in the family—especially in the A-listers' bunch.

So, in honor of National Siblings Day let's take a moment to look at these smokin' hot brothers and sisters.