In Can't Tell Me Nothing (2), he is seen welcoming Katie home from the hospital along with Maya and Margaret. When Katie reminds them that she needs surgery for her knee, he tells Katie that they are proud of her for making it as far as she did. He brings a chair over for Katie to sit on, and takes her crutches, leaning on them while he is standing.
In Hollaback Girl (2), after Katie overdoses on oxycodone, he and his wife send their older daughter to rehab.
In In the Cold, Cold Night (1), he interrupts Maya practicing cello to tell her to play quietly as Katie is resting.
In In the Cold, Cold Night (2), Mr. Matlin finds Maya sneaking out to attend her cello audition for an Indie Band. He inquires about what she's wearing, and is also curious as to why her audition is being held at a bar. He manages to persuade her to not go to the audition.
In Zombie (2), Katie mentions him when she ask Maya about the video and what she will think when their parents find out. He is again mentioned by Zig that he is going to be livid at Maya when she throws her cello in a dumpster.
In Summertime, he is mentioned by Maya when she says that him and her mom are not going to let her go to Paris. He is mentioned again when he lets Maya go to Paris again.