How do you handle your partners child?

My partner and I both have a child. Mine is 17 and his is 7. With my child he doesn't really have to deal with him because he's a teen and just does his own thing and independent.

His kid on the other handle is a lot. Talks back, doesn't listen, throws tantrums and it's difficult at times. A sweet kid for sure but I'm finding it difficult to handle because I can't parent his kid because it's not my place. So when they start throwing a tantrum I just look the other way and have him deal with it. But it's so often that it's getting hard for me to ignore. And we're talking about living together and building a life together but I don't know if I can handle years and years of this type of attitude. He tries to talk to his child to correct them but I don't know how much it sticks.

I know each child is different and parents are different. But it's getting to the point that I'm thinking about ending the relationship because it's hard for me to accept a child that refuses to listen, gets mad when they don't get their way and can't say thank you when I do something.

Help! How do I handle this or cope with this situation?

How do you handle your partners child?
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