Walmart is known for high wages.
For the Uber/Ubereats and other gig economy estimates, $11/hr is well above the industry take home.
Walmart is in progress of raising it's minimum wage to $11/hr, 22% more than federal $7.25 minimum wage. The Times covered this in the past https://www.nytimes.com/2015/02/20/business/walmart-raising-...
http://www.globalissues.org/article/26/poverty-facts-and-sta...
Walmart has turned, e.g., food assistance programs into a subsidy for themselves.
Car? What car? You are walking, biking, riding the bus.
It's doable, barely, just barely and there will be troubles if anything comes up.
I doubt it.
But none of those things were specified in OP's post.
Go look at the size of a log cabin, they were about the size of a single bedroom today and large families lived in them.
The amount of money and extra time that we spent on just one baby was astounding - clothes, doctor visits, food. Many more trips to the store/pharmacy/doctor, etc, than normal.
The USDA's child cost estimator [0] says that raising a child in the midwest costs about an extra $12000 a year, on average. Not all of that breakdown may apply, but even if you were to ONLY look at food costs, an extra $1500/year in food (when you're only making the hypothetical $800/month discussed in the GP) is not "a little".
I want to emphasize in this context (gig delivery) that the recent UberEats Stockholm posting indicated even less than $5/hr.