Honestly I don’t think it will make much of a difference . It sounds like they all have Feline herpes ( often mistaken for cat flu) your doing the right thing by cleaning their eyes.
If I’m working out the dates correctly I’d say they are nearly 3 weeks old now.. I’ve treated kittens as young as 4 weeks old with L-lysine . If the eye discharge gets worse and looks a greenish/ yellow colour then there’s probably a secondary bacterial infection. This is what happens when a cat/kitten get a herpes flare up and it’s then that you need to get L-Lysine into their system so it can control the herpes virus.
Like human herpes as soon as the virus is in their system it never leaves but the flare ups tend to die down once a kitten reaches a year or two old and after that it’s only times of stress of illness that may cause a flare up.
In the mean time the naturally occurring L-lysine in the goats milk might help but ideally getting the L-lysine in the health food shop would be good.
500mg once daily for young kittens (4 weeks or younger) you can divide that between two bottle feeds and when they are all over 5-6 weeks of age I would give 500mg twice daily. Most L-lysine you can buy is already in 500mg capsules that you can just pull apart and sprinkle the powder into the milk or into wet food and mix in.
Feline herpes flare ups can reoccur several times in a short time period so the last thing you want to do is let them get to the point where anti biotics are need ( yellow pussy eyes) and any time a kitten has to take antibiotics you need to replace the good gut flore that the antibiotics kill off again goat milk and goat milk yogurt is amazing for that too. With out mother cat they have been left with very little good gut flora and that’s extremely important in helping with neutrition obsorbtion .