the functon and meaning 'of' can it be replaced by 'for'?

Question

The problem with simply adopting any popular method of parenting is that it ignores the most important variable in the equation: the uniqueness of your child. So, rather than insist that one style of parenting will work with every child, we might take a page from the gardener’s handbook. Just as the gardener accepts, without question or resistance, the plant’s requirements and provides the right conditions each plant needs to grow and flourish, so, too, do we parents need to custom­design our parenting to fit the natural needs of each individual child. Although that may seem difficult, it is possible. Once we understand who our children really are, we can begin to figure out how to make changes in our parenting style to be more positive and accepting of each child we’ve been blessed to parent. <Nurture by Nature: Understand Your Child's Personality Type>

What's the meaning and function of 'of' and why this preposition 'of' was used?

1. Who becomes 'positive and accepting'?
2. Can I replace 'of' with 'for'?

Answer 1

I think the core confusion here is that "accepting" can be used on its own.

I'm positive and accepting.

These are traits that describe me. I think you expected this kind of usage, and that "parents should be positive and accepting," and then the sentence explains why, "for [the benefit of] their children."

But "accepting" is used there without a complement. What are we accepting? Oh, you know, everything in general. But it can also be used with a complement, just as the verb "accept" is usually transitive, to say what you're accepting of. And note, I just used "of." Because that's the common usage (I'll just go ahead and steal Quack E. Duck's link from the comments).

So the construction really says "Parents should be two things: 1) positive, and 2) accepting of their children."

Answer 2

Short answer - no. "Of" and "for" have distinct meanings and are generally not interchangeable, although mixing them up is a common mistake.

There are contexts where either makes sense, even though they mean different things. For example, "a love of music" and "a love for music" essentially mean the same thing, but technically one means a love that is related to or stems from music and the other means a love that is directed towards music. But that similarity of meaning doesn't work in every context - for example, "a cup of tea" and "a cup for tea" are very different - only one of the cups actually contains tea!

'Of' has many uses, one indicating the attitude or disposition someone has towards something. That is what you see in your example - the attitude of acceptance is towards 'each child'. 'For' does not carry this meaning.