I don't think citronella collars are cruel, don't keep the collar on at all times...A dog's nature is to bark, so keeping them from barking at all times isn't very nice. I used the citronella collar on Miko for a very short while when he was younger, but he's over 10lbs, so he's a little more sturdy...I don't know how big your baby is...Citronella is non-toxic anyway. It worked very quickly.
If he would see my husband outside or could hear him, he would go nuts and bark and bark. He would make himself sick, and he'd puke, and hurt himself very badly. Nothing else worked. Not shaking pennies in a jar, not spraying him with water. It was horrible. I felt so badly for him.
The citronella collar helped him understand that it was okay not to bark, and it helped him with his nerves. It doesn't spray into their face, it sprays out, and I guess he didn't like the smell because when it would spray, he would stop barking. And eventually, he wouldn't get all nervous when someone was outside. After those first 2 weeks or whatever it was, I never put the citronella collar on him again. He's not that jittery nervous doggie he used to be
He never ever barks anymore and he is very relaxed. This is not for everyone, but it worked for Miko. I don't mind barking, but he was literally making himself sick. Again, I'll say though, I don't think the citronella collar should be on at all times because dogs by nature bark. They like to alert their owners that someone is at the door or things like that.