The school needs a yes by Friday. You read the letter in English. They will read it in Spanish, or the other way around. The group chat already has a paragraph about uniforms and a heart. Nobody has said which after-school slot you are taking.
A household decision that crosses a language is still one decision. Write it so the person who did not open the letter can answer without reconstructing it.
One choice, in words they will use
Choose the response shape first. If someone must sign, that is a decision. If you want their feel before you call the office, that is an opinion. If you already drafted the reply and want the holes, that is a review. Do not mix them.
Close the list. Example: after-school slot A (3:00–5:00) or slot B (4:00–6:00), by Thursday evening. State your lean and what would change it. "I lean A unless you cannot do the 5:00 pickup." Write the names both of you already use for the school, the child, and each other — not a private nickname from a contact list.
Write for a cold reader. They may not have the letter. Put the date the office needs, the two options, and the one number that decides it. If a figure is the ask, write the figure in both languages. Do not leave the money in the language that feels faster to you.
Your read — that they already agreed in the kitchen — is an assumption. Mark it as one. A remembered nod is how Friday arrives with two different plans.
One send, their language for the ask
Write the ask in the language they will answer in. A summary in yours can sit under it if you need it for yourself. Two packages, one per language, is two deadlines and two answers that can disagree.
They need no account. The mail is the product. They reply from the mail or the page. You approve the wording. The session may still have a joke about their mother. That joke stays.
If they already have a RelayLink account, you need an accepted contact first. Everyone else is email.
Do not attach the school PDF. Quote the sentence that names the choice. If they want the file, they ask.
Do not put a private nickname in the package. Use the name they answer to at home.
What a sufficient reply is
"A." "B, I can do 6:00 pickup." "I need the office number; I will call Thursday." One line. Say that is enough.
Then a default you already live with. "If I do not hear by Thursday evening, I will hold A and write the office that we need until Friday noon." A default that signs their name on silence is a surprise.
If you write in one assistant and they write in another, they still read one briefing. Their chats do not merge.
This is not a conversation about whose English is better, or whose family should have been told first. Those are different messages, and often better in the room.
When the letter is sitting in a session and the chat is already in the easier language, connect your assistant and send the one household decision both of you can point at.