Question

1. He didn't bother to let me know the fact.

2. He didn't bother letting me know the fact.
(Are both grammatical?)

3. Why didn't you bother to care for the boy?
4. Why didn't you bother caring for the boy?
(Are both grammatical? Can we use 'to do' or 'ing' after the verb 'bother'?)

Answer 1

though sometimes awkward, gerunds and infinitives are usually interchangeable. They both function as nouns, after all.