My dog seems threatened by babies crying (and all high-pitched noises for that matter)

[MISTY ESCOBAR]

Hello.  Our 3 1/2 year old doodle is such a good dog. He is obedient in all things, except going crazy when we have a visitor. But...there is one thing that worries us.  He seems to feel threatened by high-pitched sounds.  I'll give a couple examples:

1.  When we are watching the tv, if he hears screaming, a baby crying, high-pitched laughter, etc, he runs up and jumps up to the tv barking.

2.  We were playing a board game, and one family member fell to the ground laughing loud and high-pitched. He didn't attack harshly, but he ran over and and got on her and she felt like he almost bit her ear.

3.  Twice, when we have had guests with babies and toddlers, he has reacted to the high-pitched crying and/or noises.  Once he did bite at a boy's ear. The other time, he put his paws up and knocked over the toddler.  If a small kid runs, he also gets over excited, and we have had to hold him back, so he doesn't knock the kid over.

Again, he is the sweetest dog. There's just this one issue. Our biggest worry is with the babies and children. We have family moving in with us for a few months next Spring. They have two small girls, under 3. 

How do we train him to not react to these sounds and to be gentle with young kids and babies? I feel that if we can train him to not be so excitable with visitors in general, that might be a first step, but we definitely need to find a solution, so that he doesn't hurt anyone. That would be terrible.

Thanks!