I think it's just Fuyumi and Natsuo, because i think his mom would still be in the mental hospital, especially with all the news around
If you look back, there was a shadow behind his sister and she glanced back at it
If you check page 18, there is definitely someone there with them. I can't think of anyone else that would put that look on Todoroki's face.
I see it now, I looked back, and yeah, now I think it's his mom, you cans ee it's the same hair outline as his mom
Do we think it might be Todoroki's mom that is coming in behind his brother/sister? I'm sitting on pins and needles here people!! (╯°Д °)╯╧╧