Dave,
Labs are retriever stock so they have the 'grab' instinct but not the 'kill' one, makes them (usually) very safe around kids and pets (we have cats and the dogs will hang back when the cat is eating from their bowl!) Our older Lab grew out of chewing at 12 months – the worst bit is having to wait for it to stop before you can repair banisters, walls, doors etd. etc. Things like remote controls just go in the bin. She and my stepson's Staffy are both good as gold with kids.
The younger one is boistrous, but slowly calming down. She had the plug off the fridge today, The chew-stop must have worn off, luckily she pulled it out of the socket before chomping the wire clean through. She has an amazing bite – several leads, collars and two seat belts, all gone with one >chomp< and you can almost loft her off the ground when she has her teeth into a toy. I think the pedigree lies and she's 50% Pit Bull.
Neil
P.S. Would never leave any dog alone with an infant though.