Sick toddler

So my 3 year old has a fever and a cough and now I’m really worried for my 1 month old who so far has no fever and isn’t showing any signs of sickness. Basically I’m just looking for any advice for those who may have experience? They both have been sleeping in my room, my 3 year old still doesn’t sleep in his own bed and my daughter is in a bassinet in my room. I’m trying to figure out how to make this work at night til he’s better.