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I've asked this here but its too old to migrate so I'm asking again.

I'm creating a list of family members:

Mother: Jane
Father: John

Biological, Justin, 5/20/1981
Biological, John,   1/20/1987
Adopted,    Jane,   8/12/1989 *
Step,       Doug,   12/1/1979 **

When listing out the type of sibling, the word step seems odd. I've always used it as step-brother or step-sister but never on its own. Is there a better choice of word to use?

*  Not biologically related to the mother or father.
** Biological child to one of the parents, not the other.
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Justin, unless the table you show is a subset of a larger table (i.e. table of siblings) then to me none of the classifications make sense as shown(i.e Jane is an "Adopted" what?). In my mind it would be better to name the entire relationship (Biological Brother, Adopted Sister, StepBrother, FosterBrother, etc.) – Andy Hatchett Dec 6 '12 at 17:41
@AndyHatchett - This would be on a Family list. I'll update the question – Justin808 Dec 6 '12 at 18:12
What about Half-blood? – ACProctor Dec 6 '12 at 18:13

You have added the

** Biological child to one of the parents, not the other.

that was not in your original question.

As Ezri pointed out, that makes your word "step" completely wrong. Doug would be a half-brother to Justin, John and Jane, and not a stepbrother. However, there is no such thing as a "half-son". Doug is a son to one parent, and a stepson to the other.

The way most genealogy software works, and the way you would normally represent the situation you describe, Doug would not be considered part of this family. Doug would be part the family of either:

John and John's first partner, or
Jane and Jane's first partner

Assume it's Jane and Jane's first partner. Then what you would have is:

Family 1
Mother: Jane
Father: John

Biological, Justin, 20 May 1981
Biological, John,   20 Jan 1987
Adopted,    Jane,   12 Aug 1989

Family 2
Mother: Jane
Father: whoever it is, or unknown

Biological,  Doug,   1 Dec 1979

Notice I also changed the date format. You should NEVER use mm/dd/yyyy which can easily be mixed up with dd/mm/yyyy.

Normally "biological" is assumed and need not be stated. I prefer to state "child" rather than biological, and advancing that further prefer "son" or "daughter" over "child".

If you still wanted to list the four children together as a non-traditional family, because they lived together for some period of time, then I'd describe it this way:

Mother: Jane
Father: John

Son 1,                Justin, 20 May 1981
Son 2,                John,   20 Jan 1987
Adopted daughter,     Jane,   12 Aug 1989 
Son of John and John's first partner or
Son of Jane and Jane's first partner,    Doug,   1 Dec 1979

As you can see above, there is no simple way of describing non-traditional family members as part of the family. You could also say:

Son of John but not Jane    (or Jane but not John), or 
Son of only John            (or only Jane)
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To make sure I'm answering with precision, I'll cover two notions that are sometimes confusing: half- and step- relationships.

  • A man and a woman, each with children, marry again. The husband's children become the new wife's "step-children"; these children have a "step-mother" (and vice versa). The children of these completely different sets of parents are then "step-brothers and step-sisters."

  • If/when those same parents now have children of their own, the newborns will be half-siblings (half-brothers or half-sisters) to all the children born to the parents' other unions (and vice versa).

The question incorporates an "adoption" circumstance. This part of the question may devolve into different notions of how we define the family, but I'll take a stab.

Adoptive relationships are between parents and children. Once adopted however, they are the sons and daughters of that parent. In genealogy this would often be reported as "son (adopted)" or "daughter (adopted)."

If the adoptive parent remarries, all his/her children become the step-children of the new spouse. (With those children's relationships to parents separately defined.)

If the adoption were to happen after parents with children were to re-marry, then they would most likely both be adoptive parents, thus the adopted child would be the "son (adopted)" or "daughter (adopted)."


For more information about how modern genealogies include and number complex family relationships, see Joan F. Curran, Madilyn C. Crane, and John H. Wray, authors, edited by Elizabeth Shown Mills, Numbering Your Genealogy: Basic Systems, Complex Families, and International Kin, rev.ed. (Washington: NGS,2008).

See also the Wikipedia entry "Stepfamily" and the various references it provides.

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GeneJ, can you quote any references for these definitions? I ask because the these, and other relationship terms, have changed over time. Hence, the description you see in a census cannot be treated verbatim with a current definition. In-laws is another case with variation. – ACProctor Dec 6 '12 at 22:04
@ACProctor-I found a Wikipedia article that isn't bad; has references. Will update and include. – GeneJ Dec 6 '12 at 23:26

The complication that we face is that we are trying to use and adapt terms devised for simple biological relationships (parent and child) to describe increasingly complex legal and social relationships. As you have found, the fit is not always ideal.

Consider the two "households" shown here. (I will avoid the term "family" to exclude even more complications). The diagram shows children (R, M, N, W, X and I) born to parents (P {now deceased}, Q, U, V and H) in various combinations and a child (J) adopted by V and H. Hypothetical blended families

This illustrates some of the possibilities now inherent in modern blended families.

Examining Household #1

  • Q & U are the birth parents of M & N
  • M and N are siblings
  • U is a step-parent of R
  • W is a step-child of Q
  • R and W are step-siblings
  • R and N are half-siblings

Now consider Household #2

  • N is a half-sibling of X
  • U is the birth-parent of X but the legal relationship may or may not be than same as with W
  • Relationship (if any) between Q and X is defined by Family Law in the relevant jurisdiction. (It "might be" step parent.)
  • W is a half-sibling of I but R, M and N have no relationship to I
  • J is the adopted child of V and H
  • The only term for the relationship between X and J and I and J is adopted sibling.

Now consider the possibility that the households apparently defined are true only as a snapshot in time. On weekends or during school holidays, either or both of W and X might be located in the other home. Many of the tidy assumptions made in the statements above now need to be reconsidered.

When you consider the additional permutations that arise when the principal care-giver of a child might be a grand-parent and that the other "children in the family" are not siblings but cousins (or even uncles), it becomes clear that the available terminology is being stretched to the limit.

In these circumstances, a family historian needs to think about not only the "correct" definitions for terms but also the ways in which the children might have used those labels to refer to themselves.

I am reminded of a family tale of a great aunt whose vast brood would describe themselves as "his, hers and ours". It might be frowned upon today, but apparently it worked.

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If one of your biological parents are also a biological parent of the sibling then they are a half brother or a half sister. If your biological parent married someone who had a child or children from a prior relationship then these would be a step brother or a step sister. I suppose but have never observed this being done, if someone wanted to make the term of step sibling sound better, brother by marriage or sister by marriage could be a valid alternative.

Hope this assist you. : }

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