Today is the official day for your annoying big brother or your bratty little sister. Yes, today is none other than National Siblings Day. Just a little backgrounder, the National Siblings Day is a celebration annually held on April 10 in honor of the love-hate relationships we have with our siblings.

Hollywood is just another family affair for some celebrities. Below is a list celebrities who have hot brothers and sisters you ought to know this National Siblings Day!

#5 Kendall and Kylie Jenner

The teen reality stars are more than just sisters-they are indeed the best of friends. Seems like everywhere the aspiring model Kendall goes, Kylie Jenner follows after. The age gap of the two is just two years hence the closeness of the two. While they might be partners in crime, Kendall and Kylie are also partners-in business! The teen stars have been trying to unleash their entrepreneurial spirit by investing in their own shoe and clothes line.

#4 Dave and James Franco

Albeit being more popular than his younger brother Dave, James is definitely one supportive brother. The two are at par in good looks and talent. Dave has starred in movies such as "Warm Bodies" and many other films.

# 3 Adam and Michael Levine

If you did not know, Adam has an equally hot brother-Michael Levine. For all of you who have swooned just by hearing Adam Levine, wait until you see his equally hunky brother Michael. That's oozing sex appeal plus two for the Levine brothers.

#2 Prince William and Prince Harry

What could get better than being royal? Being handsome of course! Prince Harry and William have long been the fantasy of people because of their good looks and wit. As if their royalty and regal looks weren't enough, the brothers are equally talented and generous-taking after, of course, their lovable mother, Princess Diana.

# 1 Alex and Emma Watson

What's better than an Emma Watson? A male version of course! Fans have been raving about the brother of Emma Watson-a splitting image of the actress. Fans would think that Alex is a twin of Emma but in reality, Emma is a few years older. The younger brother of Emma Watson has been featured in various designer brands alongside his gorgeous sister.