already have a big appetite, so work off of that fact. possibly, make kittens interact with you to get their reward (their food). pull their food dish as close to you as possible, and stay with the kittens until they are finished eating. when they are finished, pull the dish away with you. remember, always leave water out for them.
after that, create body contact with them while they eat. possibly, it would be good to pet them gently around their head and shoulders while they snack. you can also place a dish of food in your lap and let the litter to climb in to get it.
after a short time, 