I Heart Arlo features positive and affirming portrayals of LGBTQ+ characters, including a non-binary character (Bertie) and a gay character (Marcellus). Their identities are presented with dignity and are integrated into the narrative as accepted and valued members of the main character's found family, contributing to a diverse and inclusive environment.

I Heart Arlo features Alia, a transgender girl, as a main character. Her identity is portrayed positively and matter-of-factly, integrated seamlessly into the narrative. The show depicts her with dignity and agency, fostering an affirming and accepting environment for her character.