One of the most common errors I see with students is the inconsistent capitalization of the word mom and dad. This tells me that there is a fundamental misunderstanding of the rules surrounding capitalization.
The words of relations such as mom, dad, grandma, aunt, and so on do not get capitalized when used to talk about the person as in “my mom” or “my grandpa.” They do get capitalized when they are being used in place of the person’s full name.
I like to bake with Grandma.
Capitalize Grandma because you could replace it with her name: Mary. I like to bake with Mary.
I like to bake with my grandma.
Do not capitalize because you cannot replace it with her name: Mary. I like to bake with my Mary.