O cochilo da tarde ajuda o bebê a ficar menos nervoso.

Yes. Cochilo means nap or short sleep, especially during the day.

In this sentence, o cochilo da tarde means the afternoon nap.

A few related words:

• cochilo = nap
• soneca = nap, also very common and a bit cute/casual
• sono = sleep / sleepiness, not specifically a nap

So:

• O bebê tirou um cochilo. = The baby took a nap.
• Estou com sono. = I’m sleepy.

Portuguese uses definite articles much more often than English.

So where English might say:

• Afternoon naps help babies...

Portuguese often prefers:

• O cochilo da tarde ajuda o bebê...

Here, o means the, and it makes the phrase sound natural and complete in Portuguese.

You will notice this a lot in Portuguese:

• O café faz bem. = Coffee is good for you.
• A música ajuda a relaxar. = Music helps you relax.

Even when English would sound more general, Portuguese often still uses o/a/os/as.

Da is a contraction of de + a.

So:

• de + a = da

That means:

• o cochilo da tarde = the nap of the afternoon = the afternoon nap

This kind of contraction is extremely common in Portuguese:

• de + o = do
• de + a = da
• de + os = dos
• de + as = das

Examples:

• o fim da semana = the end of the week
• a porta do carro = the car door

Because the subject is singular: O cochilo da tarde.

The main noun is cochilo, which is singular, so the verb must also be singular:

• O cochilo da tarde ajuda... = The afternoon nap helps...

If the subject were plural, the verb would change:

• Os cochilos da tarde ajudam... = Afternoon naps help...

Again, Portuguese often uses articles where English may not.

So:

• o bebê = the baby

In this sentence, o bebê is the object of ajuda:

• O cochilo da tarde ajuda o bebê...
• The afternoon nap helps the baby...

This is very normal Portuguese. You will often see:

• A mãe chama o bebê.
• O médico examinou a criança.

After ajudar, Portuguese often uses the pattern:

• ajudar alguém a + infinitive

So:

• ajudar o bebê a ficar menos nervoso = to help the baby become less nervous = to help the baby be less fussy/nervous

Here:

• ajuda = helps
• o bebê = the baby
• a ficar = to become / to get / to be

More examples:

• Isso ajuda a dormir. = That helps you sleep.
• Ela ajuda o filho a estudar. = She helps her son study.

In everyday Brazilian Portuguese, people sometimes omit this a in speech, but the standard form here is ajudar alguém a fazer algo.

Because ficar usually expresses a change of state.

So:

• ficar menos nervoso = to become less nervous / to get calmer

If you used ser, it would sound more like a permanent characteristic:

• ser nervoso = to be a nervous person by nature

But here the idea is that the nap changes the baby’s state:

• before the nap: more upset
• after the nap: less upset

That is why ficar is the natural choice.

Not exactly in the same way English uses nervous.

In Brazilian Portuguese, nervoso can mean:

• nervous
• agitated
• tense
• upset
• irritable

For a baby, menos nervoso often sounds more like:

• less fussy
• less cranky
• less upset
• calmer

So the literal translation is less nervous, but the natural meaning in context is often calmer or less irritable.

Because it agrees with bebê, which here is being treated as masculine:

• o bebê
• menos nervoso

In Portuguese, adjectives usually agree in gender and number with the noun:

• o bebê nervoso = the nervous baby
• a bebê nervosa = the nervous baby girl

If the baby were clearly female, you could say:

• A bebê fica menos nervosa.

If the sex is unknown or general, masculine is often used by default:

• o bebê
• nervoso

No. Bebê can refer to a male or female baby.

You can say:

• o bebê for a male baby, or as a general/default form
• a bebê for a female baby

Then the adjectives change accordingly:

• O bebê está calmo.
• A bebê está calma.

So in your sentence, o bebê suggests either:

1. a male baby, or
2. a generic baby in a general statement

A simple pronunciation guide:

• cochilo ≈ ko-SHEE-loo
• bebê ≈ beh-BEH

A few details:

• In cochilo, ch in Portuguese sounds like English sh
• The stress in cochilo is on chi
• The accent mark in bebê shows the stress falls on the last syllable: bé

So:

• co-CHI-lo
• be-BÊ

Yes, absolutely.

Soneca is another very common word for nap, and in many contexts it sounds just as natural as cochilo.

So these are both fine:

• O cochilo da tarde ajuda o bebê a ficar menos nervoso.
• A soneca da tarde ajuda o bebê a ficar menos nervoso.

The meaning is basically the same. Depending on region, family habits, or personal preference, one may sound more natural than the other.

Yes. The sentence is already natural, but there are several everyday alternatives.

For example:

• O cochilo da tarde deixa o bebê mais calmo.
• A soneca da tarde ajuda o bebê a ficar mais calmo.
• Depois do cochilo da tarde, o bebê fica menos irritado.

Sometimes Portuguese prefers a positive idea like mais calmo instead of menos nervoso:

• mais calmo = calmer
• menos nervoso = less nervous / less upset

Both are correct. Mais calmo may sound a little more natural in many everyday situations.

The structure is:

• O cochilo da tarde = subject
• ajuda = verb
• o bebê = object
• a ficar menos nervoso = infinitive phrase explaining what the nap helps the baby do

So literally it is:

• The afternoon nap helps the baby to become less nervous.

A useful pattern to remember is:

• [something] ajuda [someone] a [verb]

Examples:

• A música ajuda a relaxar.
• O remédio ajuda o paciente a dormir.
• A rotina ajuda a criança a se acalmar.

This is a very useful Portuguese structure for talking about what helps someone do something.