My cat gave birth two weeks ago and I noticed that her kittens keep sneezing and they take a long time to find her nipples. Is it possible that the kittens have a URI and thus a clogged nose = decreased sense of smell = difficulty finding the nipple?

I'm also wondering how long should each nursing session last? They usually breastfeed for less than five minutes every three hours and sometimes just give up looking for the nipple. Please help I want to make sure they don't end up undernourished, or worse, dead.

One of them died last week and it was a very traumatic experience that I don't want to go through again. This is all very new to me and it's making me very anxious. I would really appreciate if someone could share some guidance.