Vi hjälper varandra när någon blir sjuk.

Varandra means each other or one another.

So:

• Vi hjälper varandra = We help each other

It is a reciprocal pronoun, used when the action goes both ways between the people involved.

Compare:

• Vi hjälper honom = We help him
• Vi hjälper varandra = We help each other

In this sentence, varandra is the object of hjälper.

Hjälper is the present tense of the verb hjälpa.

• att hjälpa = to help
• hjälper = help / are helping

So:

• Vi hjälper varandra = We help each other

Swedish verbs do not change for person the way English verbs sometimes do. The same present-tense form is used with all subjects:

• jag hjälper
• du hjälper
• vi hjälper

Because hjälpa works directly with an object in Swedish, just like help often does in English.

• Vi hjälper varandra = We help each other

You do not need an extra preposition here.

This is similar to English help someone, not help to someone.

När means when here.

So:

• när någon blir sjuk = when someone gets sick

Depending on context, när can sometimes feel like when or whenever in English. In a general statement like this, English might naturally interpret it as:

• We help each other when someone gets sick
• or We help each other whenever someone gets sick

Both capture the idea.

Någon means someone or anyone and is used for a person.

• någon = someone / anyone
• något = something / anything
• några = some / a few

So in this sentence:

• någon blir sjuk = someone gets sick

Because the sentence is talking about a person, någon is the correct form.

This is a very common question.

• är sjuk = is sick
• blir sjuk = becomes sick / gets sick

So:

• någon är sjuk = someone is sick
• någon blir sjuk = someone gets sick

In your sentence, blir sjuk focuses on the change of state: a person was fine, and then becomes ill.

Because sjuk is an adjective, not a noun.

Here it comes after blir and describes the person’s state:

• någon blir sjuk = someone becomes sick

You would only use en or ett with a noun, not with an adjective by itself.

Compare:

• Han är sjuk = He is sick
• Han är en sjuk man = He is a sick man

In your sentence, sjuk is a predicate adjective, so no article is used.

Because this is a normal subordinate clause introduced by när.

In a Swedish subordinate clause, the subject usually comes before the verb:

• när någon blir sjuk

That is the normal order:

• när = when
• någon = someone
• blir = gets/becomes
• sjuk = sick

If you said när blir någon sjuk?, that would sound like a question:

• När blir någon sjuk? = When does someone get sick?

So the word order in your sentence is the standard statement order inside a subordinate clause.

Yes, in informal spoken Swedish, varann is a common shorter form of varandra.

So you may hear:

• Vi hjälper varann när någon blir sjuk.

This means the same thing.

In writing, especially in more neutral or formal contexts, varandra is usually the safer choice.

Usually it means the group is mutually supportive.

It does not have to mean that every single person helps every other single person in a perfectly symmetrical way. It normally expresses the general idea:

• We help each other
• We support one another

So in this sentence, the meaning is that when one person gets sick, the others help out.

A simple approximate pronunciation for an English speaker is:

Vee YEL-per VA-ran-dra nair NO-gon bleer shook

A few notes:

• vi sounds like vee
• hjälper starts with a y-like sound: YEL-per
• varandra has stress on -ran-
• någon is often pronounced roughly NO-gon
• blir sounds a bit like bleer
• sjuk has a sh sound at the start and a long vowel: roughly shook

Exact pronunciation varies a bit by accent, but that approximation will help you get started.