What about a lovely Cavalier. Jack russells can be very lively and demanding, My gran has two of them and the eldest is very calm and the 3 year old is very lively and yappy
I walk my cavie for 20mins a day and then a nice long walk twice on the weekend. Hes lovely with other dogs, and doesn't malt at all. Hes very much a lap dog and loves his cuddles. Also a greyhound would be good, but they are quite big. I work at a retired greyhound rehoming centre and they can be very excited when people visit, but most of the time they just lay in there bed and snooze.
Whatever you choose, make sure its the perfect choice.
Good luck.
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