A mi sobrina le encanta ese juguete y duerme con el muñeco todas las noches.

Because encantar works like gustar, not like love in English.

In English, my niece loves that toy makes my niece the subject.

In Spanish, the structure is more like:

• That toy is delightful to my niece
• Ese juguete le encanta a mi sobrina

So in this sentence:

• ese juguete = the grammatical subject
• le = to her
• a mi sobrina = clarifies who her is

That is why Spanish uses le encanta rather than making mi sobrina the subject of encantar.

Yes, they both point to the same person, but this is normal in Spanish.

This is called clitic doubling. Spanish very often uses:

• an indirect object pronoun: le
• plus the full phrase: a mi sobrina

So:

• le encanta = she loves it / it delights her
• a mi sobrina = makes it explicit that the person is my niece

Using both sounds natural and is often preferred. The full phrase can add:

• clarity
• emphasis
• disambiguation

Without a mi sobrina, le encanta ese juguete would still be grammatical, but we would only know that someone loves the toy.

Because the verb agrees with ese juguete, which is singular.

With gustar-type verbs, the verb agrees with the thing being liked or loved, not with the person who feels it.

So:

• Le encanta ese juguete = That toy delights her → singular subject → encanta
• Le encantan esos juguetes = Those toys delight her → plural subject → encantan

A very common learner mistake is to try to match the verb with mi sobrina, but that is not how encantar works.

Ese is a demonstrative adjective meaning that.

The basic contrast is:

• este = this
• ese = that
• aquel = that over there / that one farther away

So:

• este juguete = this toy
• ese juguete = that toy
• aquel juguete = that toy over there

In real usage, the exact distance can be physical or just conversational. Ese often refers to something already mentioned, known, or mentally pointed out.

Also, in modern standard Spanish, these demonstratives normally do not take accent marks when used as adjectives, so ese is correct.

They are related, but not identical.

• juguete = toy, a general word
• muñeco = doll, toy figure, stuffed figure, or character-like toy depending on context

So the sentence first refers to the object generally as that toy, and then more specifically as the doll / toy figure.

This is very natural. English does the same kind of thing:

• She loves that toy and sleeps with the doll every night

It suggests that the toy in question is specifically a muñeco.

Because Spanish often leaves subject pronouns out when they are not needed.

The verb form duerme already tells us it is:

• third person singular = he / she / it sleeps

Spanish is a pro-drop language, which means subject pronouns are often omitted when the meaning is clear from context.

So:

• duerme = sleeps
• ella duerme = she sleeps

Both are possible, but leaving out ella is usually more natural unless you want extra emphasis or contrast.

The natural meaning is that my niece sleeps with the doll.

This can confuse learners because in the first part:

• ese juguete is the grammatical subject of encanta

But in terms of meaning, the sentence is about my niece and her feelings. In the second part, duerme is understood to refer to mi sobrina.

Native speakers understand this from:

• context
• real-world logic
• the overall topic of the sentence

A toy does not normally sleep with a doll, so the intended subject is clearly the niece.

If someone wanted to make it extra explicit, they could say:

• A mi sobrina le encanta ese juguete y ella duerme con el muñeco todas las noches
• A mi sobrina le encanta ese juguete y mi sobrina duerme con el muñeco todas las noches

But the original version sounds natural.

Spanish often uses the definite article el / la / los / las where English might use a possessive like his / her / their.

Here, el muñeco means the doll, but in context it is understood to be her doll / that doll.

So Spanish prefers:

• duerme con el muñeco

rather than always saying:

• duerme con su muñeco

Using su muñeco is possible, but it can sound less natural if the reference is already clear. The article is very common when possession is obvious from context.

Todas las noches means every night or every single night.

It is a very common time expression in Spanish. Spanish often uses these expressions without a preposition:

• todos los días = every day
• todas las semanas = every week
• todas las noches = every night

You can also say cada noche, and it means almost the same thing. The difference is usually just style and nuance:

• todas las noches = every night, very common and natural
• cada noche = each night, also correct

No preposition is needed here, just as English says every night, not in every night.

Yes. Muñeco is a masculine noun.

Forms include:

• el muñeco = the doll / toy figure
• la muñeca = the doll, if feminine

But be careful: muñeca can also mean wrist, depending on context.

So context matters:

• La niña juega con una muñeca = The girl plays with a doll
• Me duele la muñeca = My wrist hurts

In your sentence, el muñeco is masculine, so it probably refers to a male doll, a toy figure, or a stuffed character.

Yes. Spanish word order is flexible, especially with gustar-type verbs.

These are all possible:

• A mi sobrina le encanta ese juguete
• Le encanta ese juguete a mi sobrina
• Ese juguete le encanta a mi sobrina

The most natural choice depends on what you want to emphasize.

In your sentence, starting with A mi sobrina sets up the person we are talking about right away, which feels very natural in context. It highlights my niece as the topic of the sentence.