The first Hotel Transylvania hinted at a traumatic backstory for Dracula that involved the death of his wife Martha, indicating that what happened to her is why he's so protective of his daughter, Mavis. The 2012 movie made something new of the monster genre, featuring supernatural and typically feared creatures as the protagonists of the family-friendly animated movie that launched a franchise. The monsters exist very similarly to humans in that they have dreams, families, and histories. Dracula's family history is Hotel Transylvania's most hard-hitting story.
In the first movie of the franchise, Dracula is a single father and the owner of the Hotel Transylvania. While making plans for his daughter Mavis' birthday (who is turning 118 years of age), a lost human traveler named Jonathan stumbles upon his premises, much to Dracula's horror. Whilst Jonathan is not really fazed by Drac, Drac is evidently bothered by having a human around. When Jonathan sees a portrait of ''Lady Lubov'' in the hotel, he says that there's a legend about her: she met a lonely count and the two had a baby before they both died in a mysterious fire. However, Drac corrects this story and tells Jonathan that that's not how she died.
''Lady Lubov'' is actually Martha, Drac's late wife, and her death is not so mysterious as the legend tells. In a flashback, it's made clear that Drac (Adam Sandler), Martha, and baby Mavis were mobbed by humans who had found out they were vampires, setting their castle alight. Drac leaves the burning castle and attempts to reason with the humans when he hears a horrid scream. It's never confirmed what happened, but it's strongly implied that Martha either died in the fire started by the humans or that someone had snuck in and attacked her. Contrary to the legend, Drac and Mavis survived, but, sadly, Martha perished.
It is Drac's sad history that persuaded him to build Hotel Transylvania. Newly wary of humans, he wanted a place where monsters could feel safe, and more than anything, to shield his daughter from potential harm. Martha's tragedy is made even worse when it is disclosed in the film that Dracula and Mavis don't actually drink human blood like the classic Universal monsters, but blood substitutes, so Martha's death was spurred by unwarranted hatred. Dracula's past makes it easy to empathize with why he's so protective of Mavis, and originally so cautious of Jonathan. Drac correcting the legend and telling Jonathan what really happened was a huge step for his character, showing vulnerability to the thing he despises the most: a human. It eventually works in his favor as Jonathan proves himself to be a sweet boy who loves Mavis and her family and has no intention of hurting them. Drac's character arc benefits from this and he learns to accept his grief.
Dracula works through his hatred and desire for control once he sees how Martha and the human Hotel Transylvania character ''zing'' for each other. Underneath it all, he's a scared father who wants to keep his daughter safe, but he realizes that his experience with humans has clouded his judgment and that the best way to make her happy is to let her experience things for herself. Dracula's ''zing'' for Martha never really goes away in Hotel Transylvania and her death ultimately evolves from a lingering reminder of the danger of humans to a testament of growth.