ticks

There are a lot of different things to do -- and no I wouldn't have a preventic collar on around a baby. 
 
But I'd ask you first ... is this dog outside ALL day?  (your post kinda sounded like he only comes in at night).  I'd be restricting where this dog could go if he's getting THAT many ticks right now.  It's a bad tick year -- but it would be worthwhile to walk him elsewhere or keep him closer to the house. 
 
I've done various things -- even Skin So Soft bath oil (Avon) mixed with alcohol and water and applied (shake first) with a mister before the dog goes out helps reduce what will jump on. 
 
If your tick year is heavy where you are -- you may want to try Frontline Spray or you may have to reapply more often -- see what else your vet has.  Ticks are nasty -- if you do a search on here you'll find a lot of alternatives -- someone posted an herbal/essential oil blend they're having good luck with and I didn't note it well enough to reference it. 

Frontline doesn't repel ticks. It kills them once they are on your dog. My vet said if you are using Frontline and you see a tick on your dog, just leave it so the frontline can work and kill it. That's safer than pulling them out -- you can possibly leave the head in your dog's skin and if you squeeze the tick when you're pulling it off that can cause the tick to spew it's poison into your dog.