I am not ashamed to admit that in my boyhood I was a bedwetter. That is a theme frequently encounterd in films. Nothing especially noticeable therefore.
Recently, however, in no less than three films I viewed there was a related phenomenon: a boy wetting his pants from sheer fright.
Is this realistic? Do boys really wet their trousers when emotions get at them?
Surely you will recollect one or more of these filmed situations.
I would certainly like to read your comments.

It can and does happen when a kid is terrified but only some kids do it, not all.

Sure it can happen to boys just as it can an adult. I have never personally had that problem nor have I ever witnessed it happen to anyone I knew growing up. I guess me and my generation were just a tougher breed of boys.

Once, I have found a list on internet on the subject "Wet pants or bed". I have updated this list when I discovered this subject in a movie, without distinction between pants or bed. Sometimes no image is shown but the subject is only mentionned.

Without any garanty, with imdb reference

imdb            title
0118539      3 ninjas: high noon at mega mountain
0092425      A Perfect Spy
0100660      A Sons Promise
0350178      A swarm in may
0264100      Abandoned
0101264      Abraxas, Guardian of the Universe
0126143      allumettes suédoises [Les]
0071129      Amarcord
0163651      American pie
0086896      Angel
0115553      Anton
0088050      Army brats
0101373      At play in the fields of the lord
0092593      Au revoir les enfants
0271935      August 15th
0112461      Basketball Diaries [the]
0120601      Being john malkovich
0142342      Big daddy
0112508      Billy madison
0068286      Bless the beasts & children
0094761      Blob [the]
0317842      Broken wings
0188030      butterfly's tongue [The]
0401085      C.R.A.Z.Y.
0229290      Captive
0099235      Cellar [the]
0106535      cement garden [The]
0115891      Christmas every day
0064037      christmas tree [The]
0156408      Class trip
0094886      Clownhouse
0215681      Crazy
0462244      Daddy day camp
0255920      Dennis
0074404      devil's playground [The]
0495824      Dorm
0247303      Down
0817538      Drillbit taylor
0456062      Elisabeths Kind
0923688      Ezra
0361596      Fahrenheit 9/11
0083920      Family Rock
0106332      Farewell My Concubine
0083929      Fast Times at Ridgemont High
0118526      First do no harm
0108504      For a lost soldier
1031930      Foster child
0083976      Funeral Home
0119167      Funny games
0093072      Garbage Pail Kids Movie [the]
0099724      Génial, mes parents divorcent
0175680      Goodnight mister tom
0065794      Grandmother [the]
0368774      heart is deceitful above all things [The]
0099764      Herman
0395804      Hidden flaws
0070079      hideaways [The]
1319569      Home
0256103      Intimacy
0852970      Je déteste les enfants des autres
0107277      Josh and s.a.m.
0123930      Julian H. entführt - Qualen einer Mutter
0320042      Kamchatka
0116746      Kardiogramma (added on 20 Feb. 2009 )
0091375      Lamb
0110316      Lazarus
0119512      Left Luggage
0492473      Little Red Flowers
0875149      Lockie Leonard
0074814      Loneliest Runner [the]
0116908      long kiss goodnight [the]
0100050      Look Who's Talking Too
0391309      Lyubovni sanishta
0175880      Magnolia
0110443      Major payne
0119658      Mendel
0323243      Mich will ja keiner
0198753      Michael landon, the father i knew
0388154      Mickybo and me
0097890      miracle in valby [The]
0156812      My dog skip
0408019      My Father's House
0089606      My life as a dog
0370986      Mysterious skin
0065695      Naked Childhood
0113998      Nonnie & Alex
0079638      Norma Rae
0102585      Omen IV: The Awakening
0076517      Padre padrone
0098059      Papa est parti, maman aussi
0174106      Pardon my pups
0117555      Perfect Circle [The]
0082912      Pixote
0067591      Please Sir!
0105159      Power of One [the]
0069158      Rage (1972)
0117438      Ransom
0039651      Record of a Tenement Gentleman [The]
0289765      Red dragon
0100469      reflecting skin [the]
0107100      sacred mound [The]
0310123      Schöne tage
0339635      Schwabenkinder
0314624      Science fiction
0111102      Second best
0387575      Seed of chucky
0470290      Silly Age [the]
0107349      slingshot [The]
0339707      Song for a raggy boy
0169257      Speak Like a Child
0094070      Summer Camp Nightmare
0140594      taking of pelham one two three [the]
0086425      Terms of endearment
0264457      Thatched memories
0105576      They've Taken Our Children: The Chowchilla Kidnapping
0124207      thief [The]
0100772      Think Big
0168394      Torniamo a casa
0077138      tree of wooden clogs [the]
0202236      Tribulation
0293667      Tsatsiki - friends forever
0819675      Tumble Dry
0250797      Unfaithful
0358243      Uroki v kontse vesny
0232899      Verschwinde von hier
0111626      Vildbassen
0112923      Village of dreams
0477916      Viva Cuba
0084503      wall [the]
0120484      Waterboy [the]
0361309      We don't live here anymore
0118158      White Squall
0103268      Willies [the]
0094347      Year My Voice Broke [the]
0391539      Yeoseot gae ui siseon

Bed wetting scene from movie Kardiogramma (1995)

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