Birthday Boy Justin Long Loves to Get Silly With Girlfriend Amanda Seyfried

Since Amanda Seyfried and Justin Long got together last Summer, they have showed off their silly sides together. From goofing off in celebrity charades to taking funny photo-booth snaps, they know how to make each other laugh. On the flip side, they also cuddle up in sweet moments, whether they're watching the US Open or walking Amanda's dog, Finn. They didn't make their red carpet debut until last month, but they've been showing their love for one another for much longer than that. To celebrate Justin Long's birthday this week, relive their cutest moments — so far! Source: INFphoto.com

Amanda and Justin love to cuddle up.
INFphoto.com

Amanda and Justin love to cuddle up.

They hold hands while walking her dog.
INFphoto.com

They hold hands while walking her dog.

And stay close when the weather outside is frightful.
Getty | Alessio Botticelli

And stay close when the weather outside is frightful.

Sometimes they ride on Justin's Vespa.
Pacific Coast News Online

Sometimes they ride on Justin's Vespa.

Or hang out courtside at the US Open.
Getty | Uri Schanker

Or hang out courtside at the US Open.

They make each other laugh.
INFphoto.com

They make each other laugh.

It's pretty adorable.
INFphoto.com

It's pretty adorable.

Here they are cuddling again!
INFphoto.com

Here they are cuddling again!

They play games like celebrity charades for charity.
Getty | Dimitrios Kambouris

They play games like celebrity charades for charity.

And steal moments behind the scenes.
Getty | Dimitrios Kambouris

And steal moments behind the scenes.

They share sweet looks.
Getty | Walter McBride

They share sweet looks.

Sometimes on red carpets . . .
Getty | Bruce Glikas

Sometimes on red carpets . . .

They're pretty great at selfies.

They're pretty great at selfies.

Well, sometimes.

Well, sometimes.

They love a good photo booth, too.

They love a good photo booth, too.

And last, but certainly not least, they're great at #TBT.

And last, but certainly not least, they're great at #TBT.