So with Noe coming out and it's about a movie about Ladybug and Chat noir I'm going to assume Mylene's dad is working on the movie but something goes wrong and he gets akumatized also random but to think that his wife left him but yet he taught his daughter good values and works multiple jobs to provide for himself and his wife , cannot be someone else.
Mylene has no idea how lucky she is to have Fred. Like, seriously, she's young. I don't think she comprehends.
That would be a great episode idea. Have her realize how lucky she is to have a father like Fred. They can use learning more about Gabriel as the spark for it.
Then in a future episode have André being a pos and Zoé struggling and have Mylene have a lightbulb moment back to Depression and an 'Oh AWTA' moment.
That's how you do a three part lesson with a side character