Nice to know which ostriches you are looking for.
14325 is a male ostrich introduced in 2004 by Schleich but without refering the gender.
In 2009 it received a chick
#14398.
In 2010 an ostrich
#14610 specifically marketed as a male was added to the family.
So, the
#14325 acted as a female although it is a male.
As the most obvious difference is the color and Schleich gave male colors to it, I think it is the best model to use as a female while a real female is not released. It is not your mistake, it was Schleich mistake.
If I find the
#14091 I will let you know. I think your favorite childhood toy should be part of your collection. The rest of the family will be happy of seeing the grandpha back, especially all those cute great grandsons.