see... an 8 year old SHOULD be taught to treat ALL adults with respect.
When an 8 year old is told "this person is very special to me and thus deserves a higher level of respect, he/she DOES it.
All this shit about "I can't stop my 8 year old from saying mean things to this person" is silliness. You put their legoes in the blender if they try that shit. Then you put their Playmobile in the blender when they say it again. If you have to, you smash the iPad too. Soon, the kid will be playing with dirty laundry and empty water bottles, and will have learned to STFU and show respect to his elders.
I treat my 8 year old with complete respect, and I expect/get the same. If i was shagging a lady and he came up with "this bitch ain't my real mom, screw her", I'd be handing out his toys to his classmates, lol, the liittle shit

seriously, he wuld want to be nice to her because she was important to me. Parents that can't control their kids dropped the ball along the way - you don't suddenly have an 8 year old that is out of control. He was out of control at 7, he got away with everything at 6, he was spoiled at 5, he was allowed to scream and hit at 4, etc etc.
IF a single mom has an out of control 8 year old, you know 2 things are true...
1) She is the problem, she let that happen
2) Kid will be out of CONTROL by age 12, he will be runnnig streets and doing crime and maybe even using steroids and meth, the 2 most dangerous compounds known to man.