Boy mom question !

I am a mom of 2 little boys. When my oldest was young occasionally I noticed his penis was erect sometimes. Not often at all and come to realize when talking with dr this is normal. Fast forward to my second son, I’ve noticed that he has not had the same occureneces. As a mother is this something I should bring up to the dr? I just want to make sure he’s healthy and all is functioning. I should also mention he was born with a penile adhesion, my second son. Both boys were circumcised. Thank you