1. When you were first introduced to his charm as Tommy on 3rd Rock From The Sun.
2. Seriously, wasn't he the cutest kid ever?
3. And then when he went on to star in your favorite teen rom-com 10 Things I Hate About You.
4. And you fell in love with him all over again.
5. When he teamed up with Neil Patrick Harris to perform a skit about love and it was legendary.
6. When he took this adorable selfie while marching to raise awareness about climate change.
7. When he explained why his lovestruck character in 500 Days of Summer isn't exactly a great role model.
8. When he absolutely slayed a Nicki Minaj song during a lip sync battle.
9. Even though his real singing voice is beautiful.
10. Actually, he's adorable whenever he shares his musical talents.
11. When he took this selfie:
12. When he played with puppies and you literally melted.
13. When he brought Sally Field as his date to the Oscars because that's just the kind of guy he is.
14. Pretty much whenever he smiles.
15. Or any time he makes a funny face.
16. When he shared his motivation behind choosing movie roles.
17. When he stopped by Sesame Street to inspire young minds.
18. And finally, when he performed a strip tease on "Saturday Night Live".
And it was really, really hot.
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