Extremely stressed about RSV

I have a 6 year old, a 22 month old, and an almost 2 month old. My oldest caught RSV and passed it to my 22 month old. They’re both miserable. About to take my middle child to the ER. I’m so stressed out that my newborn will catch it. We’ve tried our hardest to keep them quarantined in their room/ the living room and our newborn in our room. I’m so scared. Has anyone’s newborn caught RSV and had an easy time with it? He got the vaccine a little over a month ago. He was born at 38 weeks exactly. No other health issues.