behavior/spits up

Question
My father-in law used to breed Boston Terriers.  He passed away quickly last year leaving behind one litter of puppies, mom, dad, and other adults dogs.  On the same day the mom and dad of this litter where hit by the same car and didn't make it.  After a few hours I went and got the puppies and brought them to our home.  The smallest had cleft lip and palate, but had been nursing fine other than messy and noisy.  I began to syringe feed all three of these babies.  They all made it fine.  The smallest with the deformity had to fed by syringe alot longer than they did.  When they were about 5 months old I sent them back to my mother-in law except the small one with problems I couldn't let her go.  We loved them all and wanted to keep all of them, but it was too much work.  We also have a sheltie and three cats that all stay outside.  And I have 4 kids and work.
Anyway Dakota (cleft lip/palate puppy) is now over a year old.  She used to sit anytime we asked her to and would get in her cage whenever you told her to, but now she doesn't seem to want to listen.  She'll just look at you like "do I have to"  if you go to her to tell her she'll just roll over on her back and not seem to hear anything else you say.  You physically have to pick her up to get her to move at all.  She is so loving and sweet.  She thinks everyone that comes over wants her in their lap.  she often even gets in my 10 year old autistic daughter's lap which is unusual as she can be a bit rough with animals and doesn't understand.  But she has picked my 3rd child as her favorite.  He is very small for his age (same size as his small 10 year old sister)they run and play together; my son will even put her toys in his own mouth and act like another dog to play with her.  Dakota loves everyone, but I need her to obey.  She has taken a liking to running cars (influenced by sheltie) and loves to stay outside.  I need her to come when ANY of us call and learn to stay out of the road.  How do I get her to behave/obey more?  
Also I've noticed she throws up alot when she eats anything other than dry dog food.  Do you think this is from her condition or needs treated?  her chest bones sink in and I'd like for her to gain a little weight.  
Her siblings are still bigger than her, but I don't know if they throw up/spit up any.  
Thanks for any advice,
Alice

Answer
Hello, Sounds like she could see a vet about her clefe palate and vomiting and being underweight as well, Also boston terriers are not dogs you can trust off leash at all, Bostons also cant be outdoor dogs you havent said if your boston lives outdoors all the time but these are indoor dogs because of there short muzzles they often can not breath well enough in hot or humid weather and would quickly die if left unatendted. Keeping yuor boston and or sheltie confined to a yard or a large chainlink dog run would pervent either getting struck by cars. She sounds like a Very submissive dog this is what it means when you walk over to her and she rolls over on her back...she is submitting to you..the overly submissive dogs can prove hard to train, But if you call her to you and offer a treat when she gets tehre after  afew times she should understand she gets rewarded for coming to you...you can cahnge treats to head pats or ear rubs later on. Also I'm not sure if your aware of this but ones voice should never be raised much with a boston terrier they can Not take harse punishment of course this means you should never strick the dog for doing something worng either as this creats fear in the dog and can cause over submissive behavior thou bostons are normal fairly submissive dogs to begin with. The clefe palate can be causing vomiting or vomting froth as could an enlongated soft palate...so its best to check with her vet.