The episode, which aired Sunday night, included a side plot in which preschooler Charlie has a play date with a girl named Taylor. Before meeting Taylor's parents, Charlie's father, Bob, couldn't figure out whether Taylor's mom was named Susan or Cheryl.
"Taylor has two moms!" Bob says after meeting them.
"Nothing gets past you, Bob," his wife quips.
The Disney Channel developed the storyline last year "under the consultancy of child development experts and community advisors," the network said in a statement.
Miley Cyrus, a former Disney Channel star, praised the network's declared intention to "reflect themes of diversity and inclusiveness".
"Is this true?!?!?! I commend Disney for making this step into the light of this generation," she tweeted at the time. "They control so much of what kids think! Life isn't bright sets & wardrobe & kids becoming superstars! This is INSPIRING."