children only need to

I'd say so WB. Incidentally with "to" is more nearly collo

Thank you~

You're welcome WB

Tho hope to hear from others more deeply into this sorta thing

Yes, optional. And as Dale said, it's more colloquial (although slightly less formal) to include the "to".

A stickler (pedant?) would say that the infinitive should not be split: "to access" is the infinitive, and "only" should not come between them. But this is an out-moded concept, and infinitives are regularly split today, without great harm.
Of course, if you omit the "to" in the examples given, that problem is removed, and the sentences become more elegant.

Thank you~