mid-parental
/ˌmɪdpəˈrɛntl/Cultural Anthropol. and Genetics
adjective
Of or relating to a mid-parent; equal to the average of that of each parent.
Origin
Late 19th century; earliest use found in Francis Galton (1822–1911), biostatistician, human geneticist, and eugenicist. From mid + parental, after mid-parent.