Saturday was the start of the little petty fights. It started at breakfast, when Harry received an invitation to the Burrow from Ron and Hermione. His friends were just back from Australia and their mission to restore the Grangers' memories and wanted to tell him about it. He was supposed to be going with Lucius to the Manor, but Lucius had an errand, freeing Harry to go to the Burrow.
The problem was that Draco didn't particularly like the idea of Harry hanging out with Ron. He wanted to order Harry not to go, but he didn't want to be that kind of husband, so he told Harry to go and thought himself quite generous for it. But then that generosity was thrown back in his face when his Aunt Andy decided to go with and take Teddy to boot. He was quickly growing attached to the baby and didn't want Teddy around Ron, but had no rights to the baby and was unable to do anything about it. He sternly suggested that they not take Teddy, because it wasn't safe, but no one listened to him.
Since Draco was powerless to stop them from visiting the Weasleys, he stirred up trouble the only way he could think of: he told Harry to offer Kreacher to the Weasleys. The Gaunt family house elves had shown up accepting his offer to be their master, resulting in too many elves at the Villa. He needed to move some of the elves over to Grimmauld Place, which would be easier if Kreacher wasn't there. Giving the elf to the Weasleys would solve that problem, and piss Hermione off. Hermione would in all likelihood take her upset out on Ron Weasley, which what Draco was aiming for with his passive aggressive tendencies.
At the Burrow, Ron had seen Draco's latest interview with the Quibbler and the invitation to Bellatrix's funeral and been extremely upset with Harry. Harry didn't like it either, even though Draco was planning to hand over a list of the worst attendees, and was easily persuaded by Ron to crash the funeral. They spent most of their visit planning how to do so, coming up with a scheme to use Ron's deluminator to transport them to Draco's side during the funeral. Draco, naturally, would have to be kept in the dark for the plan to work. Hermione warned that Draco wouldn't like it, but Harry was going forward with it anyway.
Unfortunately for Draco, Harry came home with news that Hermione had gotten upset with Ron about Kreacher, but Bill and Fleur had come to the rescue by agreeing to take the elf. And there was something off about Harry, but he couldn't put his finger on it. That only prolonged his foul mood. Then Harry was off again for the rest of the day, this time going with his father to work on the wards for Malfoy Manor. And even though this was an activity he approved of, he was once again left home alone with three babies, one he didn't even have the right to refuse Weasley visitation. He resented always being left at home while everyone else got to go out.