15 year old made a short film of her baby sister for school and now wants to post it

It's genuinely lovely. Two minutes of the little one trying to climb onto the sofa, with music and titles, for a school project. Her teacher gave it full marks. Now she wants to put it on her public account. Her friends have seen it and keep telling her to. I'm not comfortable with the baby's face out there for everyone, but I also don't want to be the amma who shot down the one thing she's proud of this term. Ente ammo, these decisions. Did anyone find a middle ground? Private account only, face blurred, something like that?