stop helping her. i can guarantee she won't develop that inquisitive trait or break the endless cycle of seeking your help if you continue to help her when she can't easily find an answer to a problem.
Absolutely. She won't be able to work like that in the workplace. If she feels disgraced to ask for help, maybe you should talk to her and explain, "CS is hard. No one should be ashamed to ask questions." She won't enjoy working if she is intimidated by hard problems.
even beyond that, she's on semester 2. my engineering curriculum hit its hardest around semester 4/5/6. things are only going to get harder. take off the safety wheels now so that she can appropriately gauge the major she's picked.
better to figure out you want to switch majors at semester 2 than semester 6 when your problems are too difficult or time-consuming for your bro to help you out.
When I was an intern, I would ask questions to a "mentor" at my company. One day, he looked at my problem and just smiled a little, and said: "It's non-trivial, but I'm sure you'll figure it out." I took the hint, went off and indeed figured it out.
