Mating my female Maltese

Question
We have two 6 months female puppies, from two separate litters. One is a toy Maltese and the other is a standard Maltese. They are best friends. We are thinking of having the toy spayed and mating the standard. My question is: Having made the mistake of purchasing two puppies at the same time and having a he.... of a time training them to even listen to us rather then play among themselves, has left us wondering if it would be making another mistake to mate the one and not the other. Do you think if we do mate the standard would the toy become jealous and hurt the standards puppies? Not sure if we should mate any at all.

Answer
Unless you're ready to take in more puppies (there's no guarantees that you can sell or give away all the puppies), then I wouldn't breed the standard.  As far as the training, I'd recommend one on one time with each dog for training sessions.  As the dog masters a command, I'd slowing start introducing the other dog into the mix... say, behind a closed door, but where the dog you're training can smell and maybe hear it.  Give the command a few times and make sure the trainee is still paying attention to you.  Then, move the second dog a little closer, like behind a baby gate or a screen door and practice some more with the trainee.  Remember, always reward the desired behavior.  YOu'll need to do this same process with all the commands you want to teach each dog.  Good luck.