I really have to disagree with the people that say you have to learn another language before attempting Cocoa/Objective C development. As someone with a Computer Science degree I know a bit about learning how to program, and while certainly my background helped me pick up Obj C very quickly, I really don't think it's required.
Case in point: My younger brother was able to develop a simple application with zero programming experience (or help from grown-ups) and have it hosted on the App store. He's 13, had no prior programming experience, and was able to figure it out through the internet and some iPhone programming books.
For some people, all they want to do is get their feet wet and learn what programming is like by working on a fun project. I really don't think it's necessary for these people to learn C before being able to do that with the iOS platform. For the people that want to become full blown professional mobile developers, sure, learn C first, or Java to learn OOP...or better yet...go to college to learn how to program. But for what this guy and his son want to do I do not think it's required.
That being said though, if you do start having serious problems, you may have to accept that the cause is a lack of understanding of basic programming concepts and go back to the basics which may be simpler than working with Cocoa.
Well, from my point of view C may not be the best choice. I, too, have a degree in computer science (actually computer science and engineering). I, myself, didn't find learning programming particularly hard, and I started at the age of 12 - but I also did it in basic.
I also was a TA for a beginning programming class in C for computer science students. Most people had trouble with C. Some didn't, but I think, just like anything else, some people have people have a knack while others have to work harder to pick something up. Now, it could have been that I was a particularly poor TA and the teacher was also poor, but students I talked to seemed to think he was good and several students thanked me for their efforts with them in the last programming lab. Most people, certainly not all, find C at least somewhat difficult as their first programming language. Objective-C is a superset and isn't any easier.
I also think there is a big difference, intellectually, between a 13 year old and a 8 year old, or even a 10 year old.
Additionally, other languages allow you to get up and running faster with graphics, sound and UI. They may not be as flexible, but can give a better sense of reward earlier.
Of course, I'll admit, that one or more of the people involved may have a knack for programming and may be able to help the others, regardless of language used. Or they may have the dedication to push through regardless.
