Antonia Forest fans

The thing about Ginty and Catkin is that while we may see Ginty as unfairly lucky and privileged (especially in Peter's room, where she gets to be pretty, wear a Doris dress, own Catkin and flirt with Patrick), the adults are probably worried about her. She was the one who got buried during the Blitz, she had a particularly hard time during The Marlows and the Traitor, and she spent the previous holidays in the thrall of Unity Logan. The grown-ups are probably thinking that Ginty needs something to occupy her during the holidays - preferably something that will also teach her responsibility - and since she's shown signs of turning into a Pony Club type, why not buy her a pony? From the adult point of view, Nicola has hawking, Peter has various hobbies, and Lawrie doesn't need to be spoiled any more than she already is.