My cavalier has had an enlarded heart since birth, and two years ago we were told he has a heart murmur. At almost 9yrs there is a big difference in his energy levels. He's on two heart tablets daily.. He's not able to tolerate been outside on hot days, nor can he tolerate the cold weather. However he loves when it's windy and letting the wind blow on his face. It's more difficult for him to get up on the sofa's and going up the stairs isn't like it was either.. He's had health problems all his life including seizures, but none in the last year or so.. Despite all that he remains as loving and gentle as ever. He loves been carried and cuddled... He wont come when called unless there's something in it for him..:D like chicken... He goes to the fridge and hit's the door with his paw when he wants something from it. He has stolen all our hearts big time.... He's our baby..