Severus was ringing all all around the wizarding world, trying to find a suitable babysitter for Dudley and Harry whilst he went on his mission. It was a nearly impossible task - he didn't want anyone obsessed with Harry, but they needed to know about him. They had to be trustworthy, be able to protect them, and preferably have a large family just in case anything went wrong.

That was when he thought of the Weasleys. They wouldn't obsess over Harry. They had a large family. He could probably trust them. And Molly Weasley was probably the most protective woman he'd ever met - she'd been close with Lily when they were at school, and protected her when he couldn't.

The only downside - he was pretty sure she hated him.

He scribbled a quick note, deciding that he would just dump the children on her with the note and their things - he'd collect them again in a few weeks, and it was probably better to ask for forgiveness from her than permission.

He gathered all of their belongings, gave them both a big kiss and cuddle each, then dropped them off in their kitchen, disapparating just as Molly Weasley walked into the room.