Greetings in that Divine and Most Precious Name of Our Lord and Savior Jesus Christ!
Toddlers throw tantrums, that is a fact. You have to let them vent a little but you also can't cave entirely to the situation. So for me, dealing with fussy children that age is really a matter of vibe and situation nuanced approach. You have to lead a child to get them to follow, and truth be told, I'm not sure many 2-3 years fully are into the follow along when walking in situations you've mentioned. This is an instance for hand holding, carrying, or even a stroller. If she is too fussy and trying to drag you to other places, politely ( I am serious, children dig polite) but assertively bring her where y'all need to be. You can be explaining why and why not you go certain places, always make it a teachable moment. Many times if we just in a pleasant tone explain all of our actions, intentions, and purposes to small children, they buy into it. Sometimes they don't, and that is where a more assertive approach is needed. You can be strict without being stern. Again, sometimes you have to let them vent, sometimes you have to let them know pouting does not get their way. However, it really all does start at this age 2-3. At this age they learn the appropriate at inappropriate ways to express their emotions and assert their own will. When we cave to tantrums, we teach them that anger and crying wins battles, and when we don't explain all our actions carefully and every time, we can leave them wondering exactly what they are expected to do.
This is just toddler advice in general, honestly your sister don't sound like too much trouble, just a bit curious
If you hold her hand and let her lead you around but within the range of the direction you need to be going, explaining what all you see is and asking her questions all the time, you will have more success. Children need to be engaged, so engage her and she will have less time to get fussy about things
Keep in mind no strategy works even a majority of the time with small children, they have more will than folks imagine. In fact, I think small children have the MOST free-will because their not yet burdened by their social obligations to other human relationships, they're just learning the ropes of social navigation.
I think in such situations we must to bring up meekness and humility in our heart, we have to be an example for our children.
When we forbid something and say the following: “not doing that”, “not say”, “not go”, child’s conscious understand this without word not, and because of that they prolong to do started step.
Instead of using not, no, we have to explain a reason of prohibition and direct our child in right
BINGO to the last part. Some good advice I was taught, when disciplining children of any age, from small children to teenagers, we always need to ask ourselves the question, "Why am I doing this?" Is it from anger? Is it a power trip issue? Why can't they do what they are asking, what really is wrong? If we have no serious answer, then as you've mentioned, it is a matter for US to learn humility. I read a great novel that said eventually we learn that children are just strangers we learn to live with. It can be so true!