Cuando discuto con mi hermana, recuerdo que hay que escuchar con calma.

In Latin American Spanish, discutir usually means to argue, not a calm exchange of ideas.

• Cuando discuto con mi hermana = When I argue/quarrel with my sister
• If you want to say to discuss (neutral, not fighting), you can say:
  • hablar de (to talk about)
  • comentar (to discuss, comment on)
  • conversar (to converse)

Both are possible, but they focus on slightly different things:

• discutir (con alguien) = to have a verbal argument; to argue using words.
• pelear (con alguien) = to fight; can be physical or verbal, but often feels stronger or more hostile.

So:

• Cuando discuto con mi hermana… = When I argue with my sister (we have disagreements, raise our voices, etc.).
• Cuando peleo con mi hermana… = When I fight with my sister (could sound more serious or intense).

After cuando, you choose between indicative and subjunctive depending on the meaning:

• Indicative (discuto):
  Used for habitual actions or things seen as facts.

  • Cuando discuto con mi hermana, recuerdo…
    = Whenever I argue with my sister, I remember…

• Subjunctive (discuta):
  Used for future, uncertain, or hypothetical events.

  • Cuando discuta con mi hermana, voy a intentar escuchar más.
    = When I argue with my sister (in the future), I’m going to try to listen more.

In your sentence, it describes a repeated, typical situation, so indicative (discuto) is correct.

Recordar means to remember, and it is normally not reflexive when it takes a direct object:

• recuerdo que… = I remember that…
• recuerdo el problema = I remember the problem.

There is also a reflexive expression:

• acordarse de = to remember
  
  • me acuerdo de que… = I remember that…
  • me acuerdo del problema = I remember the problem.

So you can say:

• recuerdo que hay que escuchar con calma ✅
• me acuerdo de que hay que escuchar con calma ✅

But me recuerdo que… ❌ is not natural Spanish (except in rare, special uses like “I remember myself” in a poetic way).

Hay que + infinitive is an impersonal structure. It means:

• one must / you have to / it is necessary to… (in general, not for a specific person)

So:

• hay que escuchar con calma
  ≈ One must listen calmly / It’s necessary to listen calmly.

Differences:

• tengo que escuchar = I have to listen.
• tenemos que escuchar = We have to listen.
• debemos escuchar = We ought to / should listen.
• hay que escuchar = People (in general) must listen / you have to listen (general advice).

In this sentence, hay que makes the idea more general, like a principle.

The structure of hay que is fixed:

• hay que + infinitive

Examples:

• Hay que estudiar. = One must study.
• Hay que comer bien. = You have to eat well.
• Hay que escuchar con calma. = You have to listen calmly.

So escuchar must stay in the infinitive after hay que.

Roughly:

• oír = to hear (the physical act; sounds reaching your ears)
• escuchar = to listen (to pay attention intentionally)

In this sentence:

• escuchar con calma = to listen calmly, carefully, attentively.

If you used oír, it would sound more like just hearing sounds, not actively listening to the other person’s point of view. So escuchar is the natural verb here.

Literally:

• con calma = with calm(ness).

In practice, it means calmly, in a calm way, without getting worked up.

Using con + noun instead of an adverb is very common in Spanish:

• con paciencia = patiently
• con cuidado = carefully
• con tranquilidad = calmly

You could say calmadamente, but:

• con calma or tranquilamente is much more natural and common in everyday speech.

Yes, but the nuance is slightly different:

• Cuando discuto con mi hermana…
  = When(ever) I argue with my sister… (general, habitual situation)

• Cuando estoy discutiendo con mi hermana…
  = When I am (in the middle of) arguing with my sister… (focus on the ongoing action at that moment)

Both are grammatically correct. For a general rule or habit, the simple present (discuto) is more typical.

In Spanish, possessive adjectives (mi, tu, su, nuestro, etc.) replace the article; you don’t use both together:

• mi hermana = my sister
• tu hermano = your brother
• su mamá = his/her/their mother

You normally cannot say:

• la mi hermana ❌
• el tu hermano ❌

(There are some rare poetic or very old uses with article + possessive, but not in normal modern speech.)

The comma separates:

• the time clause: Cuando discuto con mi hermana
• from the main clause: recuerdo que hay que escuchar con calma.

In English you also usually write:

• When I argue with my sister, I remember that…

So the comma marks the boundary between when something happens and what happens then.