I have a 14.5 week old cavalier, the breeder told us to deworm at 14 weeks we missed by one day and I saw what looked like small bits of rice in poop. Bought dewormer and gave it to her two days ago, first morning poop after deworming had spaghetti like thing looked like only one , didn't go searching! anyhow no more rest of day, then again this morning another spaghetti like thing in it. Is this how they get rid of them, morning poop, , does she need another dose in two weeks? I have young children and I am concerned for them.How do you know that it has worked, and that they are worm free.or just by giving it to her regularly take care of it,

It depends which worming preparation you use. The ones from the vet are far more effective than the ones you buy over the counter at petshops or supermarkets. I always worm my pups at 3 weeks, 5 weeks, 8 weeks, then every month till they are 6 months, and every 3 months for ever after that.

Worm eggs in poo don't become infective till 24 hours out of the body, so if you have been clearing up after her promptly, your garden should be safe despite your pup having mature worms in the gut (which it sounds like).

I forgot to say that the different products kill different types of worm. The 'bits of rice' could be tapeworm segments, and the spaghetti-like bits would most likely be roundworm. You will need a preparation that will kill both. The one I use is Drontal, but your vet may recommend another as your Cav is only a puppy.

Most cavalier people use Drontal