"Miss Step" reveals that she could dance since childhood.
In "Croaked", she and her children used to have a goldfish, but it died. She and Ronnie Anne discovered its death before Bobby, replaced it, and Bobby was fooled. Seeing as the Santiagos don't appear to have a goldfish now, but the trick apparently still works on Bobby, it's unknown what the status of the second goldfish is.
It is revealed in "Date with Destiny" that Maria was born under a water sign, making her a Cancer, a Scorpio, or a Pisces. This makes her the third Loud House character to have their zodiac sign revealed. The first was Lynn Loud Sr., who is revealed to be a Libra in "Fed Up", and the second was Ronnie Anne (Maria's daughter), who is revealed to be a fire sign in "The Horror-Scope".