toy or little breeds

Question
We just lost our 2nd Golden Retriever in a month and a half and I am
devastated.  I can't stop crying.  My husband and i are 78 and 81 and the big
dogs are just too much for us.  I love the Goldens and always will.  Can you
tell me of a toy breed with a golden personality? And one I can put under the
seat in a plane?   Very smart, won't bark and yip, not hyper;  can be a mixed
breed i.e. yorkie-poodle, chihuahua-?   I don't think I can live without a dog.

Answer
Shi Tzus are very sweet and lovable dogs and are also easy to train they not shed much but do need to be clipped and brushed,poodles are also great dog and are one of the smartest breeds and are easy to train,but again brushing and clipping may be an issue

Boston terriers are also a favorite of mine-they are also very gentle,loyal and loving,and on the plus side have short hair and low shedding