When "mom" is used like this, it's written with a capital letter. Best way to figure out if it needs to be capitalized or not is to use the character's real name in place of it, and if the sentence fits, then it's capitalized. If not, then it's written in all lower-case.
In any case, thanks for watching READING. why did i say watching. Thanks for reading. I hope to get another chapter out by Easter, but I'm not planning on pushing it.