There could be. You can search on fanfiction platforms and look for ones that are tagged as 'family - friendly' or 'general audience'. These types of stories usually avoid adult themes and instead focus on things like the emotional journey of Hanna Marin during her pregnancy, her relationships with others, and how she plans for the future with the baby in a clean and positive way.
You can start by looking on popular fanfiction websites such as Archive of Our Own (AO3). It has a large collection of fanfictions for various shows and characters. Just use the search function and type in 'hanna marin pregnant' to see if there are any relevant stories.
Well, without actually reading the specific 'Hanna and Walter A Love Story', I can only guess. Maybe Hanna and Walter met in a small town. They might have started as friends, gradually realizing their deep connection. Their love could have faced challenges like family disapproval or distance, but they overcame them and lived happily ever after.
Hanna wasn't originally a comic book. It could have drawn some influences from the comic book style or genre, but it has its own unique origin and story development.
The characters included the male lead, Hugher, a cold teenager who was ignorant of the ways of the world and hated evil! Male supporting character-Yang Nagano, a disciple of the Thousand Leaves Dojo. His swordsmanship was superb, and he had unknowingly learned the armed color of Haki. Male Supporting Actor-Sakasugi, what kind of demonic fruit did Lieutenant Colonel Michelle eat? Male supporting actor-Polusalino, if you want to live well, you can't miss your lunch break!
"A Thunder Blade Guarding Marin Fando" Author: Persimmons Horn. It's a light novel/derivative Doujinshi novel with transmigration, hot-blooded, comics, and sword cultivation elements. It's finished and can be enjoyed without worry.
[User recommendation: A weirdo in the navy. She's not a light-hearted anime transmigrator. Instead, she's a person who writes dramas in light novels. She has a headache and a big brain. She likes dramas.]
I hope you will like this book.
Another fanfic to check out is 'Marin's Melody for Link'. In this one, Marin's musical talent is at the center. She uses her music to heal Link from a strange affliction. It's a shorter fanfic but very sweet, showing the power of their connection through Marin's music and Link's unwavering trust in her.