My 'eldest' is becoming five in a week.
Here in Norway the children start state-organised kindergarten at, earliest, one year and eight months. This week my son has started saying he can't go to barnehage (kindergarten) because he has a bad stomach. And only eating lots of 'his fave' sweets would stand a chance of making him feel better, and we ought to try it . I am not sure i believe him. When i talk to the staff they say he is one of the slow ones in this regard.
Parenting is difficult. I haven't begun yet. I just try to be cool, open, and honest. I try. But it doesn't always work out that way. I'm not happy about some things and i will try harder next time i am tested. Which will probably be in the next half an hour.
Anyway, to answer the OP, that ain't grassing. That's parenting.