Why do family recipes never turn out the same whenever I try to make them?

Rice needs to be cooked as follows: Rinse the rice. Drain. Make sure the rice is fairly dried out. There should be no liquid from the rinse water.

Add one part rice to two parts boiling water AND/OR chicken broth. The water and broth need to be combined as a total, to equal two parts boiling LIQUID. Add rice to boiling liquid, stir, return the rice to a boil, then reduce heat to low, cover, and cook for 20 minutes.
Do not stir again, or keep peeking.

If you want to make fried rice, or San Francisco style rice, you should rinse and drain and dry the rice and saute it uncooked till golden brown, and THEN, AFTER that, cook it with liquid.

Rice is tricky, especially if you're not using the same exact brand and type of rice your grandma used

If the rice was crunchy you probably needed to cook it longer and low heat.

because your home wasn't the unholy ground where the demon pact was forged

You are not "real" family; you're adopted. So sorry...

You had too much water in your rice ..

Was your rice fresh?

My grandma made really good dinner rolls. As she got older my Aunt didn't want to lose the rolls so she asked for the recipe. My grandma didn't hesitate and gave it to her. No go. They just were not the same and she asked her mom if she left something out. Grandma swore that was the recipe. So my grandma and my Aunt got in the same kitchen and made them side by side with the same brand ingredients and the same oven. No matter what my Aunt did hers never tasted like my grandma's.