A little history about my Laydad Au (with sketches, yippee!)
Spoilers for The Lost Future and other games in the series
The story doesn't change much from the canon, but it does change several details.
It all starts with the disappearance of Clark and Brenda (without knowing if they are alive or dead), an almost one year Luke is left in the care of Claire and Layton, both without much knowledge of how to care for or handle a baby but they do their best for the son of their best friends.
But this is where the angst comes in (yes, this au was made mostly to be angst/comfort between Layton and Luke).
2 years pass, the time machine explodes and Claire dies in it, Layton is left completely in charge of taking care of Luke, but the pain of losing Claire blinded him too much from that duty, leaving it almost in the background of importance.
Then, the attack against Layton when investigating Claire's accident happens, and when he wakes up from his coma, he finds a very worried Luke, since he not only lost his mother figure but he almost lost his father figure and that's when Hershel realizes that although he sees Luke as his friend's son, Luke sees him as his lifelong father. Changing his way of thinking and finally accepting that he is now Luke's legal and only father.
And still afraid that they might attack him and harm him, not only him but also Luke, he makes a decision, he teaches Luke that for everyone and the outside they are apprentice and teacher, Luke Triton and Professor Hershel Layton, but in their home and close loved ones they are Hershel and Luke Layton, father and son.
And the rest remains the same! more or less.
The characters remain almost the same, only a few things change, Hershel is a little more expressive in this AU thanks to having to live with a child, when they go out he is like the canon Layton, stoic, only from time to time his more paternal and active side comes out. (For example in Monte D'or, he most likely punched the masked gentleman for hanging his son from the top floor of the tallest building in the city...) His phrase for doing those things: I may be a gentleman, but I'm also a father.
For Luke, he is still the same happy and kind boy, only now he is more careful of people because of what happened with his parents.
And Flora is in this Au! She becomes Luke's sister and they really are a nice family together :)
Well, this was practice in Krita but I discovered that it is difficult to save, in fact this is a screenshot and an animation I made was deleted... so, first and last drawing in Krita.
And this is from my AU where Luke is Layton's son, would you like to... know more about that?