How do I get the "Expected" Choice for the Family thing on Facebook?

[Ker Law]

I'm trying to put "Expected: Girl" on my Facebook Profile, but the only choices it gives me are;
Daughter
Son
Mother
Father
Sister
Brother
Aunt
Uncle
Niece
Nephew
Cousin: Female
Cousin: Male
Granddaughter
Grandson
Grandmother
And Grandfather.
How do I get the Expected choice? Someone help. Thanks!
One of my friends on Facebook has "Expected: Boy" listed on her profile.

[Stinky Man]

There is no "expected" choice sorry,.

[Tasha]

They must have just typed it in because that is not a choice