"So my kids little by little learn those from the old folks and treat it back to their parents."
What have your kids learnt from your parents?

I'm single, but I have experience in helping my mom babysitting for at least 5 babies / kids in my lifetime.

First, you have to be really patient when it comes to dealing with kids.
Try to play with them, talk with them, mingle with them.
Eventually they will treat you as a friend and always want to play with you.

Kids are ok to be playful - but you have to control their playtime.
Eyes on them all the time, and calm them down if they got too excited during playing.
Bit by bit, they will learn to play responsibly.

My parents would scold the kids (kindergarden age) if they are naughty, until they feel guilty / scared and cried. My parents never cane the kids.
When they cried, try to summarize what happened why is it wrong, and they should not do that again.
It may takes some time, but eventually they will try not to repeat the mistake because they don't want to be scolded by my parents.

Conclusion:
1) Be their "friend", play with them and in the process teach them to play responsibly.
2) Punishment is a must if they did something wrong - not necessarily cane, can try scolding them and act "garang". Then explain the rationale, let them know their fault and advise them not to repeat to avoid punishment.
3) And yes, compliment is important. Kids being kids, they will feel proud and happy if they are rewarded / complimented. This process also helps to bond you and the kids closer because they will try gain more recognition.

Hope my experience above helps / inspires you!

Maybe you can try talk with your mom and advise her to be more patience?
Yes, I agree patience is very important when it comes to taking care of the children.

Another piece of my experience: my gf's parents used to be kinda abusive to their kids.
Sometimes my gf and their siblings will get scolded or hit with no reason (the parents never bother to explain).
Over the time they became very sensitive and timid - fearing they will be punished, and have to keep guessing their parents thoughts and mood.
My gf literally had no childhood, and that's very sad...

So - either your mom have to change her attitude (be more patience, and careful with choice of words), or you/hubby change to a home-based job, or seeking help from other babysitter (preferably close relative).

In my opinion, the easiest and the hardest way is to persuade your mom to change her behaviour...