My family is surviving on one teacher's pay (70s) currently and we have a house mortgage which is quite substantial really.
We wouldn't be able to survive on just that alone. Fortunately for us, we are financially stable as we have 2 properties on rental which is generating further income for us and we are the type of people who are prudent with our money.
Still I would like to sell off one property to significantly reduce the loan. And I have plans to work part-time to supplement some income as well.
I don't think it would be easy to live off one pay alone and have 3 kids to feed.....unless you have a substantially large deposit to place on buying a house.