Quando quer comida, a gata mia tanto que até a minha irmã chega a ouvi-la do quarto.

In Portuguese, subject pronouns are often omitted when the verb form already makes the subject clear from context.

So:

• Quando quer comida = When she wants food
• The subject is understood to be a gata

Because a gata appears in the main clause, Portuguese does not need to repeat ela. You could say Quando ela quer comida, but here it would sound less natural and less elegant.

Querer is the infinitive, meaning to want.
Here you need the conjugated form because the sentence says what the cat does.

• querer = to want
• ela quer = she wants

So:

• Quando quer comida = When she wants food

The form quer is the 3rd person singular present of querer.

Mia is the verb miar conjugated in the 3rd person singular:

• miar = to meow
• a gata mia = the cat meows

So a gata mia tanto means the cat meows so much / meows so loudly / meows to such an extent depending on context.

Tanto que means something like so much that, so much so that, or to such an extent that.

In this sentence:

• a gata mia tanto que...
• the cat meows so much that...

It introduces the result of the cat’s meowing.

Structure:

• tanto... que = so much... that

Here até means even.

• até a minha irmã = even my sister

It adds emphasis: the cat meows so much that even the speaker’s sister can hear her.

So até is not about time here. It is an emphatic word meaning even.

Here chega a + infinitive is an expression meaning something like:

• ends up
• actually manages to
• even comes to
• is enough to

So:

• a minha irmã chega a ouvi-la
• my sister can even hear her / actually ends up hearing her

It adds emphasis. It suggests the meowing is strong or persistent enough for that to happen.

This is more expressive than simply saying:

• a minha irmã ouve-a
• my sister hears her

Because the expression is chegar a + infinitive.

So:

• chega a ouvir
• comes to hear / even hears

That a is a preposition required by chegar in this structure. It is not the feminine article a.

Examples:

• Cheguei a pensar nisso. = I even came to think about that.
• Ela chegou a chorar. = She even started crying / went so far as to cry.

Ouvi-la is ouvir + the direct object pronoun a (her/it, feminine singular), joined with a hyphen.

• ouvir = to hear
• a gata is feminine singular
• so the pronoun is a
• after the infinitive, it becomes ouvi-la

This happens because final -r in the infinitive drops before -la:

• ouvir + a → ouvi-la
• ver + o → vê-lo
• comer + os → comê-los

In European Portuguese, attaching object pronouns to the infinitive like this is very common and standard.

In European Portuguese, object pronouns are very often attached after the verb, especially with infinitives.

So:

• ouvi-la = to hear her

This is called enclisis.

For a learner of European Portuguese, this is very important, because it is much more common than in Brazilian Portuguese in many contexts.

So the sentence uses very natural European Portuguese structure:

• chega a ouvi-la

Because here comida means food in a general sense, not a specific meal or a specific portion of food.

• quer comida = wants food
• quer a comida = wants the food (some specific food already known)

So the sentence means the cat wants food generally, not one particular dish.

Do quarto is the contraction of:

• de + o = do

So literally it means from the bedroom or out of the bedroom, depending on context.

In this sentence, it most naturally means that the sister can hear the cat from the bedroom—that is, while she is in the bedroom, she can still hear the cat.

So:

• do quarto = from the bedroom

Most naturally, it refers to where the hearing is happening from: the sister can hear the cat from the bedroom.

In other words, the sister is in the bedroom and still hears the cat.

In real life, context would make this clearer. Grammatically, the phrase is attached to the whole idea of hearing, not just automatically to one noun.

Portuguese usually uses the definite article more often than English before nouns.

So:

• a gata = the female cat / the cat
• a minha irmã = my sister

In English, we often omit the article in some cases, but Portuguese commonly keeps it.

Also, gata specifically means a female cat. A male cat would be gato.

In European Portuguese, possessives are very commonly used with the definite article:

• a minha irmã
• o meu irmão
• a nossa casa

So a minha irmã is the most standard and natural form in Portugal.

Without the article, minha irmã is less typical in European Portuguese and sounds more like Brazilian usage in many contexts.

It can suggest either, depending on context:

• meows so much = very frequently / a lot
• meows so loudly = with enough intensity to be heard

Here, because the result is that the sister can hear the cat from the bedroom, English might naturally translate it as either:

• meows so much that...
• meows so loudly that...

Portuguese tanto leaves that slightly open and focuses on the degree or extent.

Yes, that is close to the structure, but it sounds unnatural in English.

A more natural breakdown is:

• Quando quer comida = When she wants food
• a gata mia tanto que = the cat meows so much that
• até a minha irmã chega a ouvi-la = even my sister can hear her / even my sister ends up hearing her
• do quarto = from the bedroom

So a natural English version would be something like:

• When she wants food, the cat meows so much that even my sister can hear her from the bedroom.

Yes. A simpler version would be:

• até a minha irmã a ouve do quarto
• até a minha irmã consegue ouvi-la do quarto

These mean roughly the same thing, but chega a ouvi-la is more expressive. It gives the idea of even my sister ends up hearing her / can even hear her, as if the meowing reaches that level.

So the original sentence sounds a bit richer and more idiomatic.