Teething or getting a cold?

Desiree

So this morning out LO was pretty congested and a little fussy. It’s his first week at daycare. When I picked him he was pretty drooly. They lady said he was like that a lot today and sleepy. I took his temp when I got home and it was 99.0. So really not much of a fever if any. He will is 12 weeks today and 3 months next Friday. So not sure how early babies can start teething. Hope it is that rather than him getting a cold.