diff --git a/personal/k-1_visa.md b/personal/k-1_visa.md
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--- a/personal/k-1_visa.md
+++ b/personal/k-1_visa.md
@@ -219,3 +219,120 @@ Lewisville, TX 75067-8003
 
 * [Form I-129F (PDF)](https://www.uscis.gov/sites/default/files/document/forms/i-129f.pdf)
 * [Instructions for I-129F (PDF)](https://www.uscis.gov/sites/default/files/document/forms/i-129finstr.pdf)
+
+---
+
+Here is a **comprehensive technical reference section** for the **sibling-based immigration process** in the U.S., integrated as an additional module in your larger immigration documentation.
+
+---
+
+# 👥 **Petitioning to Bring Siblings to the U.S. as Permanent Residents**
+
+---
+
+## 📌 **Overview**
+
+U.S. citizens aged **21 or older** may sponsor their **siblings (brothers and sisters)** for lawful permanent residence (Green Card). Legal **permanent residents (Green Card holders)** are **not eligible** to sponsor siblings.
+
+---
+
+## 🗂️ **Required Documentation**
+
+The **petitioner** (U.S. citizen) must submit:
+
+* ✅ **Form I-130**, Petition for Alien Relative
+  *(Only one Form I-130 is needed per sibling; do **not** file separate forms for their spouse or minor children.)*
+
+* ✅ **Proof of U.S. citizenship**, one of:
+
+  * Valid U.S. **passport** (copy)
+  * U.S. **birth certificate**
+  * **Consular Report of Birth Abroad**
+  * **Naturalization certificate**
+  * **Certificate of citizenship**
+
+* ✅ **Proof of sibling relationship**:
+
+  * Your **birth certificate**
+  * Your **sibling’s birth certificate**
+  * Both must show **at least one common parent**
+
+---
+
+## 🧾 **Special Sibling Scenarios**
+
+If the sibling relationship arises through:
+
+* **Adoption**
+* **Step-relationships**
+* **Paternal half-siblings**
+
+👉 You must provide **additional legal documentation** establishing the familial relationship as valid under U.S. immigration law (e.g., adoption decree, marriage/divorce certificates showing timeline alignment, evidence of parental legitimacy).
+
+---
+
+## ⏳ **While the Petition is Pending**
+
+> ❌ **Siblings cannot immigrate while Form I-130 is pending.**
+
+* They are generally **ineligible for nonimmigrant visas** due to **immigrant intent**, unless a strong case can be made under specific exceptions.
+* Entry to the U.S. must wait until **immigrant visa processing** is completed and a **visa number becomes available** via consular processing.
+
+For more, see:
+
+* [Adjustment of Status](https://www.uscis.gov/green-card/green-card-processes-and-procedures/adjustment-of-status)
+* [Consular Processing](https://www.uscis.gov/green-card/green-card-processes-and-procedures/consular-processing)
+
+---
+
+## ❌ **Denials and Appeals**
+
+If Form I-130 is **denied**:
+
+* The denial notice will include **instructions for filing an appeal**.
+* Appeals are submitted via **Form I-290B**, Notice of Appeal or Motion.
+* After fee processing, the appeal is referred to the **Board of Immigration Appeals (BIA)**.
+
+---
+
+## 🔄 **Following-to-Join Benefits**
+
+### Applicable to:
+
+* Spouses and/or children of immigrants **who obtained permanent residence via preference categories**, and:
+
+  * Were **married or had children** at the time of their own green card issuance
+  * Those relationships still exist
+
+### Benefits:
+
+* No need for a **separate I-130** petition
+* **No wait** for additional visa numbers
+
+### How to Apply:
+
+#### If adjusted in the U.S.:
+
+File:
+
+* ✅ **Form I-824**, Application for Action on an Approved Application or Petition
+* ✅ Copy of original immigrant petition (e.g., I-130)
+* ✅ Copy of **Form I-797** (approval notice)
+* ✅ Copy of your **Green Card (Form I-551)**
+
+> If filing **concurrently** with Form I-485, no additional documentation is needed.
+
+#### If immigrant visa was issued **via consulate**:
+
+Contact the **National Visa Center (NVC)**:
+
+* 📧 Email: **[NVCInquiry@state.gov](mailto:NVCInquiry@state.gov)**
+* 📬 Mail:
+
+  ```
+  National Visa Center, ATTN: WC  
+  32 Rochester Ave.  
+  Portsmouth, NH 03801-2909
+  ```
+
+Would you like this integrated into the I-129F reference as a single structured manual or kept as a standalone sibling sponsorship module? I can also generate it as a PDF or prepare a visual workflow for both.