Is it your own sentence? I'd say "Мой брат вам и так ничего не сказал". It's like "все равно". Anyway my brother didn't say anything. This kind of sentence often implies the continuation: "Не волнуйся, он и так (=все равно) не помнит тебя" (Don't worry, anyway he doesn't remember you"). P.S. I have to say that Эдуард was wrong here: <<it usually serve to summarize what was said before -И ТАК , начнём. We were preparing to do something , and now it is right time to start it И ТАК , мы имеем .....( we count something , and it is time to say what we have )<< Here it will be "Итак", not "И так". It's different. If you don't trust me, you can look it up in a dictionary.

According to glossary, "и так" here is used to emphasize the action in past, present of future tense. "и так" here corresponds with "и без того уже", "уже". Хотя мы и так делаем всё возможное. Мы и так собираемся сходить туда. Мы и так уже все вымотались. (вымотались = сильно устали).

That's a set pattern: так + (ничего, никого, нигде) + и не + verb which is used to say that something was expected or supposed to happen, but did not. Examples: Он учил китайский три года, но так (ничего) и не выучил Они искали этого человека, но так (нигде) и не нашли. Они искали кого-то, кто мог бы это сделать, но так никого и не нашли

Maybe the previous example was not so clear. "Ты и так (=все равно/уже) это знаешь, почему ты нервничаешь? (Anyway you know that! Why are you nervous? or You already know that)

it usually serve to summarize what was said before -И ТАК , начнём. We were preparing to do something , and now it is right time to start it И ТАК , мы имеем .....( we count something , and it is time to say what we have ) There is some other meaning - there is a few of something or it has been done enough , but else exists some circumstance , that makes that situation else lesser , or worser or more hard . Я не могу одолжить тебе денег , у меня И ТАК ничего нет ( i can not borrow to you my money , i have a few amount , even do not borrowing you . Mой брат и так вам ничего не сказал - I guess here it refers to case i described as a second- it means do not do anything more , it is useless , it will make situations just worser , my brother should not say you it anyway . Я вам и так хорошо помог - do not ask my help more , i give it as much as it would be possible .