Celeb Birthdays: April 15

Wow, it's a slow day for birthdays, people, I'm not gonna lie.

Harry Potter actress Emma Watson celebrates her sweet 16. See Emma Watson's birth chart (Astrotheme, no birth time)

Seth Rogen of the dearly departed Freaks and Geeks, as well as a bunch of other things, is 24.

Football player and Angie Harmon's baby daddy Jason Sehorn is 35.

Samantha Fox, who so courageously spoke out for the naughty girls in need of love, turns 40. See Samantha Fox's birth chart (Astrotheme)

Non-blonde songwriter Linda Perry is 41. Hey, she should totally help Samantha Fox make a comeback!

Actress Emma Thompson turns 47. See Emma Thompson's birth chart (Astrotheme, no birth time)

Supergenius artist and innovator Leonardo da Vinci would have been 554 today had his many inventions included a zombie-reanimating machine. See Leonardo da Vinci's birth chart (Astrotheme)

Birth dates from IMDB.com. Please email me any corrections, additions or -- especially appreciated! -- exact birth times.