Maybe it's because the platform you're using doesn't support that feature or there are some technical glitches. Check the settings and see if there are any specific instructions.
Maybe the story source you're using doesn't have the lyrics included. It could be that it's a licensing issue or just not part of the content provided.
It could be because of copyright issues. Lyrics are often protected by law, and adding them without permission might not be allowed. Also, sometimes the format or the nature of the story might not be suitable for including lyrics.
The 'Why can't we be friends' line in the Toy Story lyrics might suggest a struggle to bridge some kind of gap or overcome differences to form a friendly connection.
The lyrics might relate to the themes of friendship and understanding that are common in Toy Story. They could enhance the emotional connection of the story.