I agree with Yoda and forgot to mention allergies can happen if a food is introduced too soon. Many babies don't sleep the whole night and its part of being a parent, to wake up to tend the babies needs. Parents are usually exhausted the 1st year and that's expected.

Both mine were premature and I had to wake up every 2 hrs at night to breast feed them. I never gave cereal in a bottle - you're supposed to start in a bowl and not so thick by mixing a little formula....then increase thickness as the baby tolerates. What if the cereal clogs the nipple and then he'll have to suck hard....then get gas. She's looking for making her life easier, which may not be best for her baby.