At the end of the book Nahuel, the human-vampire hybrid the Cullens have just met, states that she will probably reach complete physical maturity around seven years after birth, physically appearing to be around sixteen or seventeen years old, at which point she will stop aging and live to an unknown extent.
The half-vampire daughter of Bella Swan and Edward Cullen is born during Breaking Dawn, and races through her physical maturation. According to fellow half-vampire Nahuel, Renesmee be fully grown at the age of seven.
By the end, she's like 3 and a half months old.
Seeing as she's half vampire, one would think she would age much slower than humans, since vampires can't age at all. However, poor unloved Jacob shouldn't have to wait eighteen years for his happily ever after, so Renesmee grows abnormally fast, and will magically stop aging once she reaches sexual maturity.
It's been a while since I read the book, but it was stated that while Reneesme will enjoy a much longer life thanks to her half-vampire genes, she will not live forever. It will be Jacob's aging process that will slow with hers since he “imprinted” on her.
When they phase into a wolf for the first time, they stop aging. There are plenty-a-plot-holes here BUT if Jacob maintains a regularly scheduled shape shift, he can essentially stay young forever. This is a good thing because Renesmee will be Jacob's age physically in a mere few years.
At the end of the story, Renesmee watches her family graduates and celebrates it at their home. During the celebration, Renesmee tells her parents that she and Jacob are having a baby resulting Edward to chase after Jacob.
Nahuel states that Renesmee will probably reach complete physical maturity around seven years after her birth, at which point she will stop aging and live to an unknown extent of years.
At the end of Eclipse, she becomes engaged to Edward Cullen, and they marry in Breaking Dawn, one month prior to her 19th birthday. On their honeymoon, she becomes pregnant, and, due to the peculiar nature of her baby, Bella nearly dies giving birth to their daughter, Renesmee.
Renesmee is fertile as she is 1/2 human. The only aspect of herself that is a vampire is that she'll never age after she matures and she drinks blood.
Although Edward and Bella tell him that Renesmee is an orphan that they've adopted, he discovers their biological relation when he looks into her eyes (which he recognizes as his own), but decides to stick to the adoption as their public story for their safety.
So I was watching Breaking Dawn part 1 and realized Bella's pregnancy is 28 days long.
Renesmee will eventually reach an age of maturity and stop growing, just like Nahuel, but she does have some time of growing left. Vampires are not used to growing, but Renesmee's aging process is much faster than a human's.
Jacob Black is Renesmee's husband and imprinter. He imprints on the infant Renesmee in Breaking Dawn.
Renesmee doesn't sparkle the way full vampires do, instead she has a subtle glow, making it easier for her to go out during sunny days and not draw attention.
The Twilight 6 Saga: Midnight Sun - Trailer (Renesmee and Jacob)
In the world of Twilight, vampire women are unable to get pregnant because their body can not change to hold a fetus.
Biting Bella to save her life breaks the treaty. It's not just her who will lose her life it's anyone around her because of her selfishness.
Bella has a conversation about the fate of vampires when Carlisle is tending to her injured arm in "New Moon," and in the same film, Edward explains that the main reason he doesn't want to turn Bella into a vampire is because he doesn't want to damn her.
Vampire venom is poisonous to the Quileute wolves, so they would die. But Renesmee isn't venomous. Female hybrids aren't venomous in general. I think it's actually stated in the books that renesmee bites jacob lol. So nothing happens really.
While Jacob insists his feelings for Renesmee (Mackenzie Foy) will remain completely platonic until later in her life (as does Twilight author Stephenie Meyer), Bella (and most of the fandom) find their relationship to be unsettling at best.
He would most probably die depending on how severe it was. Jacob said in Eclipse that if a vampire bit him, or one of the other shape-shifter, it wouldn't kill him, but if he already had a cut of something to that affect(combined with the venom) that could be fatal.
Fans know, in the end, Jacob and Renesmee do live happily ever after together, along with Edward and Bella. Shoutout to Alice's future-telling skills! She gave viewers a glimpse of the future at the end of Breaking Dawn: Part 2.
Bella's Anger At His Imprinting Is Hypocritical
While she's a little unsure about the concept of imprinting at first, she comes around to it after Jacob explains that even if they imprint on a young girl, like Quil, who imprints on a two-year-old, their feelings won't be romantic until she is of age.
He does but in a different way. Once he imprinted on Renesme, the love he had for Bella shifted to her child. The whole philosophy behind his love for Bella was for him to stay connected to her bc of her child. Renesme was the reason his love was so strong and unwavering.