If your toddler is sick- like cold, virus, low fever- how hard do you try to keep them away from your baby?

C was just at the ped for a check up but came down with a little virus- low fever (100-102 max), cough, runny nose, cranky. Baby is only 5 weeks old. She is breastfeeding so I'm hoping that I am building and transferring immunity to her.

I'm trying to keep her from getting in the baby's face but wondering how much of a losing battle it is.