I had TWO Boston's one was deaf (APPOLLO),one not perfectly marked(ZUESS) was the last two out of a litter of nine. Got a deal on them for less than price of one. Took BOTH because deaf one was smaller and more timid the other bigger and more outgoing but always seemed to touch his brother so when called one BOTH came: when went out side at night if called one would come and flash outside light and other came got so just turned light on and off and no calling even needed. Was so funny if was sleeping and someone came to visit when woke up would start barking and be so excited would get Zuess all excited all over again so cute They learn to adapt so well we had 4 kids and enough love to go around.