Puppy sick

Hi, me and the family have recently added two Pug puppies to our ranks, Tupac and Biggie, the problem is that after their morning food Tupac the smallest is sick most times, but usually only the morning meal, I have noticed he and his brother eat really fast, could this be the problem? We did think at first it was because he ate a small stone before but he hasn't today as we have been extra vigilant when they are out. Tupac is also the smallest of the two by a considerable size