I guess cats like humans can struggle with weight problems. We have 2 rather fluffy ones (Garfield & Rusty), Gidget is probably a tad overweight and Fluffy is my little bit. She doesn' even weigh 8 pounds, but on her it is just right. It is hard to give the ones that need the extra food because the ones that don't always seem to gobble it up. I hope your 2 big boys do well at the vets and maybe they can try a bit of the lite food. I know Purina One makes a "Healthy Weight Management" dry food. I try to give them that as a treat more often than the real treats. They think they are getting something special, but it is still good for them. Of course, now that they have discovered the Whiskas Temptations I may have spoken to soon. Anyway, Good Luck Gary! Let us know how they do.