Learn Spanish (Latin America): Cuando el bebé nazca, vamos a estar muy felices. - When the baby is born, we are going to be very happy.

Because the baby hasn't been born yet! In Spanish, when you use cuando (when) to talk about an event that will happen in the future, you must use a special verb form called the subjunctive. Here, nacer (to be born) becomes nazca to show that we are anticipating a future moment.

Where does the 'z' in nazca come from?

The verb nacer (to be born) is irregular. To form the present subjunctive, you usually start with the 'yo' form of the normal present tense. Since 'I am born' is nazco, that 'zc' root carries over to make the subjunctive form nazca (for he/she/it).

Why do we use estar with felices here instead of ser?

While ser feliz means to be a happy person in general, estar feliz means to feel happy at a specific moment. Since this sentence is about the burst of emotion you will feel right when the baby arrives, estar is the most natural choice.

Why is it spelled felices and not felizes?