I have a 7-month-old male yorkie (Jackson) who loves to eat too! He is about 6 1/2 lbs. now, and he wants to eat ALL the time. I home cook for my guys, and I feed them 3 times a day, plus leave kibble out for them all the time. Jackson will eat his cooked meals and alot of the puppy food too! Not wanting to overfeed, I talked to my vet and he said the 3 cooked meals plus the amount of kibble he was eating is fine. He's still young and VERY active. My other yorkie (Jake) is only 4 1/2 lbs. full grown. He eats smaller amounts than Jackson, but I've noticed since we got Jackson that Jake's appetite seemed to increase. This might be because he wants to keep up with his brother, but I think it's because he is way more active now that he has a brother to chase after and play with. I think the amount of activity a dog has will determine how much he eats. I know that if my guys have had a particularly busy day, they tend to eat more on those days. So, I kind of adjust their portion sizes to the amount of activity they have had. Neither of them are overweight and are very healthy, happy and active.
good luck! Paxton sure is a cutie!