WMG / Lady Bird

Kyle's biological father is Elio Perlman from Call Me by Your Name.

Still not quite over Oliver (Armie Hammer), Elio (Timothée Chalamet) copes via a sporadic string of meaningless one-night stands; one of which occurred with Kyle's mom circa 1985/1986 putting Kyle (Timothée Chalamet) right at the age he was in Lady Bird (set in 2002/2003). Since it was only supposed to be a casual one-time fling, Kyle's mom and Elio never bothered to get any of each other's info and thus Kyle's mom wasn't able to contact him upon learning she was pregnant. Whether or not Kyle was aware of Elio, he still considered Mr. Scheible his father.