Is "Ram khaana khaya" correct?

Why

Kabir's instinct may come from casual speech, where 'ने' is sometimes dropped in a hurry, making it feel optional. But in correct written Hindi grammar there is a firm rule: verbs that take an OBJECT — like 'खाना खाना' (to eat food), 'किताब पढ़ना' (to read a book) — require 'ने' with the subject in the past tense. This is different from verbs with no object, like 'जाना' or 'आना' ('राम गया', with no 'ने', because nothing is being 'eaten' or 'read' there). Test it: 'राम गया' is correct (no object), but in 'राम ने खाना खाया', 'खाना' is the object, so 'ने' is required. His sister is right: verbs like 'खाना खाना' need 'ने' with the subject in the past tense — 'राम ने खाना खाया' is the correct form.