pentu experimental gismu

x1 is a non-binary-gendered sibling of/to x2 by bond/tie/standard/parent(s) x3; [not necessarily biological]

See also: dinti, nunmu, tunba, mensi, bruna, tamne, famti.


In notes:

paznu
x1 is a non-binary-gendered offspring/child of mother/father/parents x2 [not necessarily biological]; x1 is filial (but not a son or daughter)