''I'll go talk to her.''
I'm wondering if using two verbs side by side (go talk) is grammatically correct.
Thanks in advance
The "GO DO SOMETHING" Family of Colloquial Expressions

There are several variants of "go do" in American English. All are used informally in conversation, and almost never in formal writing.

In the following discussion, the verb "do" stands for any verb, but the list of verbs normally used with this construction in everyday conversation is not very long.

Probably the three most used members of the "go do" family are the imperatives:

Go do it. Go and do it. Go ahead and do it.

(These are all used in a more relaxed style of speaking, so the "and" sounds like "in" or "un": "Go 'n do it.")

In all of these the "go" is used to show that the speaker is giving encouragement to the listener and/or calling the listener into action. The "go" can be a literal going or not. "go ahead" is more used when the going is not literal. Here the "go" is an encouragement to proceed without delay.

Go make me a sandwich! (A literal movement away from the speaker is probably necessary to get the task done.)

Go ahead and start writing the letters. (Not necessarily movement. "Don't wait to start writing. Proceed immediately to the task.")

[To a pet dog] Go get your leash and we'll go for a walk! Go get it, boy! Good dog! (Movement away from speaker.)

You should probably go ahead and call her as soon as you get a chance.
(Not necessarily movement.)

Go and see if the taxi has arrived yet. (Movement.)

All can be preceded by "just": Just go do it. Just go and do it. Just go ahead and do it.

The addition of "just" shows that the speaker is trivializing what is to be done in order to encourage the listener even more. The listener is encouraged not to consider the advisability of performing the action, not to worry about it, not to feel that permission is needed. The feel of these expressions is "Don't think! Act!"

More examples:

Go sit in the kitchen and I'll be there in a second.
Do you want to go (and) see a movie?
Go get a blanket for Grandma.
Go and sin no more. (Biblical)
Go Tell It on the Mountain. (Song title)
Guess I'll go eat worms. (Said when you feel that nobody likes you.)
Just go ask him; he's not going to bite you!
We're almost ready. Go set the table.
Just go ahead and park over there.
My jacket was torn to pieces. Now I'm going to have to go buy another one.

In the past ("went and did") or present perfect ("have gone and done"), the meaning changes, and the forms without "and" are not possible. Frequently, the meaning in this case, if not one of literal movement, is one of showing disbelief and disapproval -- a sense of "shouldn't have".

Susan went and told Jane about the surprise party. Why did she go and do that?
Jack just got paid yesterday, and he's already gone and spent it all.
Before the buffet was completely set up, Laura just went and helped herself to the crab salad.
When little Bobby spilled milk all over the floor, his mom said, "Now look what you've gone and done!"
Why did you go and leave us? (Not redundant. The "go" is the attitudinal element; "leave" is the element of motion.)

Emotion: smile
Hello CJ and Salam

['Go' + imperative] also appears in some of the older English poets.

Alexander Pope (C18) seems to have been especially addicted to it:

'Go, measure earth, weigh air, and state the tides...'
'Go, soar with Plato to th'empyreal sphere...'
'Go, teach Eternal Wisdom how to rule...'

—3 examples, from a page chosen at random.

I would think the best-known poetic instance is a translation of
Simonides' Epitaph on the Greek Dead at Thermopylae:

'Go tell the Spartans, thou who passest by,
That here obedient to their laws we lie.'

The 'dog' usage is interesting: also 'go get him, boy!' on seeing a rabbit.
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In American English it is informal but correct. After all, if 'go and do' is correct, we might as well go whole hog and say 'go do'. It only works with 'go' and 'come' though.
Thanks MM Emotion: smile
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