What You Think You Know About Vampires Is Wrong
You need to stop going to Hollywood for your folklore.
Vampires. Everyone thinks they know all there is to know about them. They die in sunlight, are afraid of crosses, can be killed via a wooden stake through the heart, don't reflect in mirrors, and can't have babies, right?
WRONG!
Once you get into the actual folklore, you'll find you're, in the words of Dr. Cox from Scrubs, "Wrong wrong wrong wrong, wrong wrong wrong wrong! You're wrong! You're wrong! You're wrong!"
Let's address the sunlight thing first and foremost.
This trope comes from the silent movie Nosferatu which states that if a woman of virtue can keep a vampire at her side until the crow of a rooster, they'll die. It's not from actual folklore, it's not even from Bram Stoker's Dracula. In fact, in the novel Dracula the character of Jonathan Harker sees the count in DAYTIME London stalking a woman in a very large hat. Obviously the count intends to have this lady who loves big hats and cannot lie for dinner. (Which, on a side note, I wish more authors would pay attention to. Since Lucy is the only vampire Van Helsing kills on British soil, that means Big Hat Lady is now Undead Big Hat Lady and still feasting on British blood.)
In stories that came before Dracula, such as Camilla by Joseph Sheridan Le Fanu the vampire in this story, while spending most of her hours indoors, is still up during the day time hours, just a bit weaker.
Varney The Vampire: Or The Feast Of Blood only states that moonlight can revive Varney, but it does not state that sunlight kills him.
Folklore itself makes it clear vampires can and do go out in the daytime. They're just not as strong. Think about 3 & 1/2 Dwayne "The Rock" Johnsons instead of 12 Dwayne "The Rock" Johnsons. Nowhere in any folklore does it say that vampires burn up in sunlight. If that were true you'd see more tales of "real" vampires bursting into flames when a coffin is open.
Religious icons - again, not in actual folklore. Yes, Stoker put this in Dracula, but when you think that vampire folklore predates Christianity and every single culture has their own version of a vampire it's actually kind of dumb. Garlic is mentioned, along with wolfsbane (yes, it's not just for werewolves), throwing grain at their feet - they have to stop and count every grain, and possibly my favorite - cow poop found in a thorn bush. Not just any cow poop will do, the cow has to have pooped in a thorn bush. Spread that on your doors and windows and you'll be sure to keep vampires at bay as well as door to door salesmen, political canvassers, and Jehovah's Witnesses.
A stake through the heart does NOT kill vampires. All this does in immobilize them. Remove the stake and they're right back to their bloodsucking ways.
Killing them is far more involved and there are many methods.
A stake through the heart to immobilize them, then cut off their head and bury it separately from the body.
Cut off their head, remove their heart, burn the heart - you can mix the ashes of the heart in water for the victims to drink to prevent them from becoming vampires. Then burn the entire body.
Silver kills vampires. Yes, it's NOT just for werewolves - in fact, silver isn't for werewolves at all. Werewolves are NOT immortal. They can die by drowning, old age, even disease - so please remember to vaccinate your werewolf! (The only thing is, werewolves come back as vampires when they die.)
An iron spike through their skull can pin them in their grave, but like the stake through the heart does not kill them.
Pin their tongue to the roof of their mouth with rose thorns so they can't feed and starve.
A branch of wild rose on their grave also holds them in place. Remove it though and they're right back to feasting.
Now as for reflections - yes, in Stoker's Dracula he says the Count doesn't reflect. However, in years upon years of reading every folklore book I could get my hands on I found no actual folklore saying vampires don't reflect. The closest I came was a belief that when a person dies you have to cover up every reflective surface in the place they died, including water, for if their wandering soul sees it's reflection they'll become trapped there forever.
That being said, let's go back to the fact silver kills vampires. If we go with that then yes, it does make sense that antique mirrors backed with silver would not reflect them. Same with film photos developed in any solution that contains silver. Modern mirrors and digital cameras though should be able to reflect/capture their image.
Babies - yep, vampires can have them. Not with each other, however, a human has to be involved. The resulting child is called a Dhampire. A half human, half vampire being that is a natural born vampire hunter. Think Marvel's Blade but without the bloodlust. Usually this happens when a male vampire has sex with a human female. It's very rare to have a female vampire get pregnant by a human male.
And yes, vampires can and do have sex. In fact, in folklore vampires don't just drink blood. They get food from other sources - namely psychic ones. They feed on this energy by causing either nightmares or orgasms. (Side note, one of the symptoms of anemia is chronic nightmares and we all know who used to be blamed for anemia....) If a human who's turned into a vampire was romantically involved in anyway before death their first victim is that romantic interest. Yes, they **** them to death. This is how a vampire can feed on the same person for months or even years.
Yep, it's not like movies and books where they kill a person a night. A vampire can just keep feeding on the same person for a long period of time.
Now, yes, vampires don't exist. Too bad, I'd rather have a world with vampires than Nazis. That being said, it is really annoying that people keep using tropes like them dying in sunlight just because one bad silent film - yes, I said it, Nosferatu was not a good movie even by silent film standards - made it popular. It's time to go back to folklore.
Vampires - that don't sparkle (only Goblin Kings are allowed to sparkle) - and are out and about in daytime.
Vampires that don't cringe at the sight of a cross.
Wooden stakes don't kill them.
There's no reason a vampire can't reflect in a modern mirror.
Not only can vampires do the deed, but they can conceive.