I'm just going to focus on the thing that I find obnoxious: I don't like when people trick others into eating foods they openly state that they don't like. I actually think that indicates a form of abuse that we see as being acceptable, and I label it as abuse because it's explicitly ignoring the body autonomy that we should all have. Children, like all people, should have a right to determine what they eat and do not eat. Tricking them into eating things because you call them by another name is just... I'm not a fan.

There are numerous reasons a person would choose to not eat something. Some people find certain textures appalling, while others can't handle certain tastes. Others just aren't ready to try certain foods, opting not to eat them at that moment. And those aren't even all the reasons that people don't like and choose to not eat certain foods.

Showing that there are no consequences (and, in fact, that you can impact someone in a 'positive' manner) by tricking them into eating food is... kind of abhorrent. It teaches kids that this is okay and that they should be able to do so. It teaches kids that they know what's best for everyone, that they should be able to make decisions for and coerce them.

This book seems initially harmless and is trying to play on the jokey tone that happens when you try to work with younger kids, but it's... just not a good look. We shouldn't be teaching kids to overstep boundaries, even if we find those boundaries to be absurd. If their sister doesn't like tomatoes, they shouldn't try to convince her to eat them; they should let her decide to eat them on her own. There may be a number of reasons why she's not eating them, and tricking her into doing it just shows they don't respect her, her boundaries, or her needs.

But that's not the lesson the protagonist learns. (And there's not even a lesson of teaching kids about healthy foods! Which could've been a better story, too.)