Andrew greatly respected his father both as a role model and family. However, he is initially submissive to how Paul control his life to ensure his future as his successor and even reluctantly casting aside his passion as a pianist for that purpose, and gradually forget the fact that he has dreams and ideals of his own that worth pursuing until Akko reminded him about it. Unlike his father, Andrew is more open-minded when it comes about magic and witches, which became evident thanks to his recurring interaction with Akko. It is then he eventually realized that he doesn't have to always agree with his father's opinion and must stand up for his own ideals.
In Tree of Leaves, Andrew finally stands up for Akko and her friends by expressing his support for them when Paul questioned their intentions. When Paul realized how wrong his initial opinion about witches and their culture in general and asked his son to share his opinions about them, the delightful Andrew stated that he'll teach him what he knows.
As children, Diana met Andrew with whom he frequently exchanged pleasantries in his summer residences. Both used to have fights about whether magic had any value at present. Despite this, they don't consider each other actual friends upon reuniting in their adolescence, especially due to their conflicting views on magic. However, their relationship throughout the series grows to that of mutual understandings, and arguments become more playful as they engage with each other on better terms.
Although Andrew respects Mr. Blackwell, the latter has lower negative opinions about the former than Mr. Hanbridge, questioning his capabilities as a viscount and future Earl. Mr. Blackwell harbors a strong grudge towards the young man in the light of him interfering in the fiasco unwittingly caused by Akko and Amanda at Appleton Academy. It's unknown whether the relationships between the two improved after the events of Tree of Leaves.
Frank is Andrew's best friend, the two of them almost always side by side whenever one of them appears. Unlike Andrew however, Frank is less callous to others and more interested in the prospects of magic and making friends, perhaps even romance, with a witch. Although initially annoyed at his friend's intrigue in the magical world, Andrew gradually considers Frank's musings and pursues his relationship with Akko and involvement with the witches on his advice.
He shows a great deal of trust in Frank, openly talking about his feelings about the witches he would otherwise hide from others when it's just the two of them alone.
Andrew initially dismissive towards Akko for being a witch, but seems to have taken interest in her after their encounter with the Arcas and their trip to the fountain. Their recurring interactions from that point brings a positive impact on the young man who realized that he has to stand up for his own ideals and magic might not as obsolete as he and his father believed to be. Andrew then in turn, reminds Akko to achieve her dreams in her own way rather than living in her idol's shadows.
Upon discovering that Akko and her friends are chasing the missile in "Tree of Leaves", Andrew stands up for the witches as he urged everyone to support them despite Mr. Blackwell's fierce objection and his father's belief that they would make things worse, though the two eventually stands down after Prime Minister expressed his agreement to the young man.
By the end of the same episode, Andrew visited Akko to return her hat.