Antes de la siesta, la madre prepara el biberón y sienta a la bebé en la trona.

Because antes normally needs de before a noun or an infinitive.

• antes de la siesta = before the nap
• antes de comer = before eating
• antes de dormir = before sleeping

You can use antes by itself when the rest is understood:

• Llega antes = He/She arrives earlier

So in this sentence, de is required.

Spanish often uses the definite article where English would not.

Here, la siesta refers to the usual nap time, not necessarily a specific one that has already been mentioned. This is very natural in Spanish.

Similar patterns:

• después de la cena = after dinner
• antes del desayuno = before breakfast
• a la escuela = to school

So antes de la siesta is the normal Spanish way to say before the nap / before nap time.

Spanish often uses the definite article with family roles when the relationship is clear from context.

So:

• la madre = the mother
• el padre = the father
• la abuela = the grandmother

In English, we often prefer her mother or the mother, but Spanish does not always need the possessive.

Both are possible in some contexts:

• La madre prepara el biberón = The mother prepares the bottle
• Su madre prepara el biberón = Her mother prepares the bottle

Using la madre sounds like neutral narration.

In Spain, biberón means a baby’s feeding bottle.

So prepara el biberón usually means something like:

• making the bottle
• preparing the milk or formula
• getting the bottle ready for the baby

It does not just mean the physical object by itself; in context, it often refers to the bottle as prepared food for the baby.

Because sentar and sentarse are different.

• sentar a alguien = to sit someone down, to seat someone
• sentarse = to sit down oneself

Here, the mother is doing the action to the baby, so Spanish uses the transitive verb:

• La madre sienta a la bebé = The mother sits the baby down / seats the baby

If the baby were doing it herself, you would use sentarse:

• La bebé se sienta = The baby sits down

So sienta a la bebé is correct because the mother is placing the baby into a seated position.

No. Here sienta comes from sentar, not from sentir.

This is a very common point of confusion because the forms can look alike:

• sentar → sienta = seats, sits someone down
• sentir → siente = feels

Compare:

• La madre sienta a la bebé en la trona = The mother seats the baby in the high chair
• La madre se siente cansada = The mother feels tired

The structure makes the meaning clear:

• sienta a la bebé = she seats the baby
• se siente cansada = she feels tired

This is the personal a.

In Spanish, when the direct object is a specific person, and often with pets or other animate beings, you usually use a.

So:

• La madre sienta a la bebé = The mother seats the baby
• Veo a María = I see María
• Ayuda al niño = He/She helps the boy

English does not have an equivalent here, so it can feel strange at first. But in Spanish, a la bebé is the normal pattern because the baby is a specific person.

Bebé can be masculine or feminine depending on the sex of the baby, and the article shows that.

• el bebé = the baby boy, or sometimes just the baby
• la bebé = the baby girl

In this sentence, la bebé tells you the baby is female.

Also, the accent in bebé is important. It shows the stress is on the last syllable: be-BÉ.

Yes. In Spain, trona means high chair, especially the kind used for feeding a baby.

So:

• en la trona = in the high chair

This is very common in Peninsular Spanish. In other Spanish-speaking countries, other expressions may be more common, such as:

• silla alta
• sillita de comer
• periquera in some regions

If you are learning Spanish from Spain, trona is a useful everyday word.

Because en marks location here.

The pattern is:

• sentar a alguien en algún sitio = to seat someone in/on some place

So:

• sienta a la bebé en la trona = she seats the baby in the high chair

You use a before la bebé because that is the personal a, marking the person who receives the action.

You use en before la trona because that is the place where the baby is seated.

The present tense here can be used for a habitual action or to describe a routine.

So the sentence can suggest something like:

• this is what the mother usually does before nap time

Spanish often uses the present for routines and general descriptions:

• Por la mañana, desayuna y sale de casa = In the morning, he/she has breakfast and leaves home

If you wanted to describe one completed event in the past, you would normally use a past tense, for example:

• Antes de la siesta, la madre preparó el biberón y sentó a la bebé en la trona

So the present tense here gives a routine or descriptive feel.

Because both verbs have the same subject, la madre.

Spanish, like English, does not need to repeat the subject when two verbs are joined by y and clearly refer to the same person:

• La madre prepara el biberón y sienta a la bebé en la trona

This works just like:

• Ana cocina y limpia
• El niño come y duerme

Repeating la madre would be possible for emphasis, but it would sound less natural in a simple sentence like this.