The duties of the wife towards her husband are
1- The right to intimacy
2- Not leaving the house without his permission (unless there is a legitimate excuse)
3- Not bringing anyone in the house without his permission
4- Not taking anything out of the house without his permission.
She does not have a duty to the in laws.
As for the kids, she has to care for them until they are 2. She is also the first teacher. She also is not responsible for feeding the kids, it is the husbands responsibility.
Also if she chooses to use birth control, she has the right to do so.