Is transferring money from the philippines to the US illegal. My bro in law says it isnt but has my wife do it?

Ok, my brother in law helps philippine people get visa's into the us and even citizenship's. As of lately he has asked my wife to receive money from the philippines only in the amounts of 8 or 9K at a time and deposit it into his banking account I was just was if this is illegal. Because almost every week he calls and asks my wife to do this because he says he has done it to many times? I just don't trust him because if it wasn't illegal he would have his wife or even himself do it. Personally I think he is laundering money. Can anyone help me with this? I don't want my wife to get into any kind of trouble we have a 3 year old daughter and both just started our careers.