Who played (without credit) little Eric Knowles in the "Emergency!" episode "Frequency", which aired in 1973?

Here's a picture of the character from that episode.

http://www.nexxie.0catch.com/EGuests/frequency_eric.jpg

This item came up after an episode synopsis hunt:

Ep # Title Airdate
1 "Frequency" September 12, 1973
Johnny's policeman friend is injured and later dies from a car accident; the delay in treatment due to another Squad tying up the bio phone frequency with a heart case leads Roy to speculate if the delay may make a difference later. The doctors treat a child (Ike Eisenmann) who turns out to be drunk. Thanks to Dr. Brackett and Dixie, Johnny and Roy assist in treating opposing members of a bike gang after a bloody rumble, and it spills over into the ER. Other rescues include a man that welded himself inside his own kinetic art sculpture, and a father and son trapped in a building collapse at a construction site. Linda Kelsey ("Billie Newman" from "Lou Grant") guest stars as the policeman's widow.

https://en.wikipedia.org/wiki/List_of_Emergency!_episodes

Unfortunately I can't find any pictures of Ike Eisenmann - if the referenced drunk child is who you are asking about.

http://www.nexxie.0catch.com/EGuests/Guestindex_frequency.html

Ike Eisenmann plays Kevin Paxton. __???__ plays Eric Knowles
Most complete list of cast I have seen. There are 24 uncredited stars listed with no names including a dog.