Mycroft had already apologized in writing that he hadn't gone shopping and thus didn't have so much as a packet of digestives to go with the tea, so he didn't feel the need to apologize a second time. He entered the living room carrying the tea tray, which he set down upon the low table in front of the sofa and began to pour. Mary didn't need to tell him how she took her tea - Mycroft remembered her preferences from watching episodes of Downton Abbey.
"When I was young, our family had an Irish Setter, which I named 'Redbeard'," he said as he poured, but then sealed his lips tightly: the topic of their family dog had come up in conversation before, when Sherlock visited him the day after the Dementor attack. He'd been emotionally compromised at the time, and had made an embarrassment of himself at the time, so he paused to check himself and make sure he wouldn't do the same in front of Mary. Fortunately for Mycroft, he was much more in control now, and in defiance, to prove to himself that he was, he continued to tell Mary, "He was diagnosed as having brain tissue inflammation and needed to be put to sleep, then that was that."
When Reynard heard this, he turned his head looked startled - Mycroft aloofness in regard to the death of his childhood pet worried the poor creature, which Mycroft realized, and immediately felt regretful for his callousness
Mycroft handed Mary her cup. "It's not necessary to train your pokemon. From what I gather in the animated show, the majority of kept pokemon are not trained for fighting. However, it's said that the process of training and battling them against others strengthens the bond between the pokemon and its trainer, in a way that nothing else will do." He held his hand down, and Reynard crossed over from Mary to sit beside Mycroft, who scratched behind his ears. "Reynard saved my life from those Dementors. When I realized that, that's when I decided such a bond was not a bad thing."