Is an efficiency living quarters suitable for childgrowth?

I live in a 4 bedroom 3 full bathroom house with 11 other family members. My girlfriend wants to move out into an effeciancy for privacy and to raise the baby in a healthier environment. My re dad and stepmother suggested I help him get a bigger house and I'll have my own master bedroom. it's just him his new wife and baby. He wants to move into a 4 bedroom 3 full bath. For only 200. My mom charges me a little more , but alot cheaper than what it would be to support a family on my own. In an efficiency which I most likely couldn't afford on a lenient budget