Minha filha está com febre, então vai ficar em casa hoje.

Because the possessive adjective must agree with the thing possessed, not with the speaker.

• filha = daughter, a feminine singular noun
• So the correct possessive is minha = my for a feminine singular noun

Compare:

• meu filho = my son
• minha filha = my daughter
• meus filhos = my sons / my children
• minhas filhas = my daughters

In Brazilian Portuguese, both minha filha and a minha filha can be correct.

• minha filha = my daughter
• a minha filha = my daughter

The article before a possessive is often optional in Brazilian Portuguese, depending on region, style, and context. In everyday speech, leaving it out is very common.

So:

• Minha filha está com febre sounds completely natural.
• A minha filha está com febre is also natural.

Portuguese often uses estar com to express temporary physical conditions.

So:

• estar com febre = to have a fever
• literally: to be with fever

This is a very common pattern:

• Estou com fome = I’m hungry
• Estou com sono = I’m sleepy
• Estou com dor de cabeça = I have a headache
• Ela está com febre = She has a fever

Even though English uses have, Portuguese often uses estar com in these cases.

Yes, but it can suggest a slightly different nuance.

• Minha filha está com febre usually means she has a fever right now, as a temporary condition.
• Minha filha tem febre can also mean she has a fever, but it may sound a little less tied to the immediate moment, depending on context.

For a situation like this sentence, where the daughter is sick today and will stay home, está com febre is the most natural choice.

Portuguese has two main verbs for to be: ser and estar.

• ser is usually for permanent or defining characteristics
• estar is usually for temporary states or conditions

A fever is a temporary condition, so Portuguese uses estar:

• Ela está com febre = She has a fever / She is with a fever

Using é com febre would be incorrect.

Então means so, therefore, or then, depending on context.

In this sentence, it connects cause and result:

• Minha filha está com febre = My daughter has a fever
• então vai ficar em casa hoje = so she’s going to stay home today

So então here means so or therefore.

Portuguese often leaves out the subject pronoun when it is clear from context.

Here, after Minha filha está com febre, it is obvious that the person who will stay home is my daughter. So Portuguese does not need to repeat ela.

You could say:

• Minha filha está com febre, então ela vai ficar em casa hoje.

But repeating ela is not necessary. The version without it sounds very natural.

Vai ficar is the structure ir + infinitive, which is a very common way to talk about the near future in Portuguese.

• vai = goes / is going
• ficar = to stay / to remain

Together:

• vai ficar = is going to stay / will stay

So:

• vai ficar em casa hoje = she is going to stay at home today

This future structure is extremely common in spoken Brazilian Portuguese.

Em casa is a fixed, very common expression meaning at home.

• ficar em casa = to stay home / stay at home

You usually use em casa when you mean home in the general sense, not a specific house.

By contrast:

• na casa = in/at the house

This is more specific and usually needs extra information:

• na casa da avó = at grandma’s house
• na casa do João = at João’s house

So here, em casa is the correct natural expression.

Yes, hoje can move around, and the sentence would still be grammatical.

Examples:

• Minha filha está com febre, então vai ficar em casa hoje.
• Minha filha está com febre, então hoje vai ficar em casa.
• Hoje minha filha está com febre, então vai ficar em casa.

The original version sounds very natural. Putting hoje at the end often feels neutral and smooth, like English today at the end.

Yes, ficar can mean different things depending on context. Two very common meanings are:

1. to stay / remain
2. to become

In this sentence, it means to stay:

• ficar em casa = to stay at home

Compare:

• Vou ficar aqui. = I’m going to stay here.
• Ela ficou triste. = She became sad.

So ficar is a flexible verb, and context tells you which meaning is intended.

Yes, febre is a feminine noun:

• a febre = the fever

Some Portuguese nouns ending in -e are masculine and some are feminine, so you often just have to learn their gender with the article.

Examples:

• a febre = fever
• a noite = night
• o leite = milk
• o nome = name

In this sentence, you do not see the article a, because the phrase is com febre, not com a febre.

You could say:

• Minha filha está com febre, então ficará em casa hoje.

That uses the simple future ficará = will stay.

It is correct, but in everyday Brazilian Portuguese, vai ficar is usually more common and more natural in speech.

So:

• vai ficar = very common in conversation
• ficará = correct, often a bit more formal or written

The lh in Portuguese is a special sound, similar to the lli in some pronunciations of English million, though not exactly the same.

• filha sounds roughly like FEE-lya

A few notes:

• fi = sounds like fee
• lh = a palatal sound, like ly
• a = a light final ah

So filha is approximately FEE-lya.

Also compare:

• filho = son
• mulher = woman
• trabalho = work

The lh sound appears in many common words.

The comma helps separate the two clauses and makes the cause-result relationship clearer:

• Minha filha está com febre
• então vai ficar em casa hoje

It works a lot like English:

• My daughter has a fever, so she’s staying home today.

In writing, the comma before então is very natural here.