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Full Siblingship Test (With Common Parent)

Full Siblingship Test (With Common Parent)

Two people checking whether they share both parents, with a known parent available

Participants:
Two Siblings, One Common Parent
Lab processing:
5 business days after the lab receives your samples
$179.99

Quantity

1 pack·$179.99/test$179.99

Order with these add-ons (optional)

Overview

A full siblingship test estimates whether two people share both biological parents. Including a known common parent (for example, a shared mother) substantially strengthens the analysis because it lets the lab account for the DNA inherited from that side.

Sibling relationships are estimated as a likelihood rather than a simple yes/no, because siblings share only part of their DNA. This is a private, peace-of-mind test — it is not chain-of-custody and not admissible in court.

What you get

  • Cheek swabs for the two siblings and one common parent
  • Step-by-step illustrated instructions
  • Pre-addressed return mailer or FedEx label
  • A private results report with a relationship likelihood by email

How it works

  1. 1

    Order your kit

    Choose your test and check out online. No appointment or doctor's order needed.

  2. 2

    We ship within 1 business day

    Your collection kit ships free with cheek swabs, step-by-step instructions, and a return mailer.

  3. 3

    Collect samples at home

    Each participant gently swabs the inside of their cheek. Painless and takes about a minute per person.

  4. 4

    Mail samples to the lab

    Drop your samples in the mail using the supplied envelope. Prepaid Return Mailer or FedEx Overnight Label Provided. Lab processing time starts when the lab receives your samples.

  5. 5

    Receive results securely

    The lab sends your report to us and we forward it to you privately by email.

Turnaround timeline

  1. 1
    Kit ships — Within 1 business day of your order.
  2. 2
    In transit to you — A few days, depending on your location.
  3. 3
    You collect & mail back — At your own pace. The clock for lab processing has not started yet.
  4. 4
    Lab processing — 5 business days after the lab receives your samples.
  5. 5
    Results delivered — Sent to you privately by email.

Accuracy & methodology

Sibling tests report a combined sibling index and probability rather than a fixed percentage. Including a common parent makes the result considerably more conclusive. Testing is performed by our accredited partner laboratory.

Testing is performed by our AABB-accredited partner laboratory.

Your privacy & trust

Your privacy matters to us, and DNA information is among the most sensitive personal data there is.

  • Samples are used only to perform the test you ordered and are destroyed after testing is complete. <!-- TODO: confirm exact sample-retention window with fulfillment lab before publishing -->
  • Results are delivered privately by email and are never sold, rented, or shared with third parties for marketing.
  • Your DNA data is treated as sensitive personal information. While at-home, informational tests are generally not covered by HIPAA, we handle your results with comparable care.
  • You can request deletion of your records at any time by contacting us.

Frequently asked questions

Why is a sibling test a likelihood, not a yes/no?
Full siblings share about half of their DNA on average, but the exact amount varies. The lab calculates how likely the shared pattern is for full siblings versus unrelated people and reports a probability.
Does including a parent really help?
Yes, significantly. A known shared parent lets the lab account for one side of each sibling's DNA, producing a clearer result.
Can this be used legally?
No. It is for personal peace of mind only and is not admissible in court or for immigration.

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Half Siblingship Test

Half Siblingship Test

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Participants:
Two Siblings (common parent optional)
Lab time:
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Avuncular Test (Aunt / Uncle)

Avuncular Test (Aunt / Uncle)

An aunt or uncle and a child estimating a biological relationship

Participants:
Aunt or Uncle, Child (mother optional)
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Need a legal DNA test?

Need results for a custody case, child support, immigration, or any other legal matter? An at-home test cannot be used for those purposes. You'll need a court-approved, chain-of-custody DNA test performed through an accredited laboratory, where a neutral third party verifies every participant's identity and handles the samples.