La pequeña come tan bien en la trona que casi nunca mancha el babero.

In Spanish, an adjective can sometimes be used like a noun when the context makes the meaning clear. Here, pequeña literally means small or little, but la pequeña is a natural way to mean the little girl, the little one, or the little child.

Because it is feminine singular, it suggests a girl or a female child. It can also sound affectionate.

A few similar examples:

• el pequeño = the little boy / little one
• la mayor = the older girl / the eldest
• el menor = the younger boy / the youngest

So this is not just describing someone as small; it is actually standing in for a noun.

Come is the present indicative of comer for él / ella / usted.

Spanish often uses the simple present for:

• habits
• general truths
• repeated actions
• things that are characteristically true

So La pequeña come tan bien... suggests something like The little one eats so well... in a general or habitual sense.

If you said está comiendo, that would usually focus more on what is happening right now at this moment:

• La pequeña está comiendo = The little one is eating right now

Here, the sentence sounds more like a general observation about how well she eats, not just a description of one specific meal.

Tan ... que is a very common structure meaning so ... that.

So:

• tan bien ... que = so well that

In this sentence:

• come tan bien ... que casi nunca mancha el babero
• She eats so well that she almost never gets the bib dirty

Why not muy bien?

Because muy bien just means very well, while tan bien ... que introduces a result:

• Come muy bien = She eats very well
• Come tan bien que casi nunca mancha el babero = She eats so well that she almost never stains the bib

Also, tan does not change for gender or number here. It stays tan before adjectives and adverbs:

• tan alto
• tan alta
• tan bien

In Spain, trona means high chair: the chair a baby or small child sits in while eating.

This is a very common word in Spain. In other Spanish-speaking places, people may use different expressions, such as:

• silla alta
• silla para bebé
• other regional terms

So if you are learning Spanish from Spain, trona is the natural word to know here.

En is used because the child is in / on the high chair while eating. Spanish commonly uses en for being seated in something or located in something:

• en la cama = in bed
• en el coche = in the car
• en la silla = in/on the chair
• en la trona = in the high chair

English sometimes uses in and sometimes on, but Spanish often just uses en in these situations.

Spanish often leaves out subject pronouns because the verb ending already tells you who the subject is, or because the subject is already clear from context.

Here, the subject is explicitly stated as La pequeña, so there is no need to add ella.

• La pequeña come... = natural
• Ella come... = possible, but only if you want emphasis or contrast
• La pequeña, ella come... = usually unnecessary

Spanish prefers not to repeat the subject unless there is a reason.

Casi nunca means almost never.

It is a very common adverb phrase:

• casi = almost
• nunca = never

Together:

• casi nunca = almost never

Examples:

• Casi nunca llueve en verano = It almost never rains in summer
• Casi nunca llega tarde = He almost never arrives late

The order is important: casi nunca, not nunca casi.

Mancha comes from the verb manchar, which means to stain, to dirty, or to get something messy.

In this sentence, it means that food does not usually get the bib dirty:

• manchar el babero = to stain / dirty the bib

Depending on context, manchar can mean:

• to stain clothes
• to dirty a surface
• to make something messy

So here it is not about a permanent stain only; it can simply mean getting the bib dirty with food.

Spanish often uses the definite article with clothing, body parts, and personal items when it is already obvious who they belong to.

So:

• mancha el babero = she stains the bib

Even though English often prefers her bib, Spanish does not always need su if the owner is clear from context.

This is very common:

• Se lava las manos = He washes his hands
• Me duele la cabeza = My head hurts
• Se puso el abrigo = She put on her coat

You could say su babero, but it would usually sound more marked, more explicit, or more contrastive. In this sentence, el babero is the most natural choice.

Yes, babero means bib, especially the kind worn by a baby or small child while eating.

It is a masculine noun:

• el babero
• un babero

That is why the sentence says el babero, not la babero.

The sentence uses a result clause:

• come tan bien
• que casi nunca mancha el babero

This follows the pattern:

• tan + adjective/adverb + que + result
• so + adjective/adverb + that + result

So the logic is:

1. She eats very neatly / very well
2. As a result, she almost never stains the bib

This structure is very useful in Spanish:

• Habla tan rápido que no lo entiendo = He speaks so fast that I do not understand him
• Estaba tan cansada que se durmió enseguida = She was so tired that she fell asleep immediately

So this sentence is a good model for expressing cause and result in a natural way.