Hello. I'd like to know if these verbs must be followed by with in this pattern:

The brothers fight with each other.
My children play with each other.
Blue and gray don't go with each other.
My girlfriend and I chatted with each other for a long time.
They don't talk with each other.
According to strict usage, these are all good if only two people are involved; 'one another' if more. However, I seldom notice which I am using when speaking.
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MrM, what's the difference between, talk to each other and talk with each other. I have seen both forms.
'talk to each other' -- suggests a goal-directed dialogue.

'talk with each other' -- suggests an extended conversation.

In most cases, they are meant to imply essentially the same thing, however.