Continuity mistake: Right after the Hawker demon attacks, Piper picks the baby up and the head of the doll is covered and you can't see the face; a quick change in camera angles shows the baby's face and the blankets are all arranged and folded to frame the baby and no time has elapsed to allow this to happen. Also, the doll used as the baby double is much smaller than the baby and is very noticeable in shots that switch back and forth between the covered doll and real baby.
Continuity mistake: When Phoebe is talking to Elise on the phone, the phone handset jumps from Phoebe's left hand to her right hand, then back to her left. (00:20:40)
Continuity mistake: In the opening scene in the club with the DJ playing, they have an overhead shot of the club. In the lower right hand corner we see Paige and Dave talking with Leo and Piper, but after the scene cuts out Piper is just walking in. This can't be since we already saw them talking.
Continuity mistake: When Paige goes to Cole for help saving Phoebe, she puts her hand on his chest. In the next shot, her hand disappears, with no time for her to have moved it. (01:11:35)
House Call - S5-E13
Continuity mistake: When Jessica approaches Paige and Glen in the church, she puts her hands on her hips. When the shot cuts to Glen and back, Jessica's arms are crossed over her chest. (00:21:30)
Answer: That was a mistake in the series.
Also, the episode is called 'Babies First Demon' and this alone tells us that it's Wyatt's first time in the field (so to speak) and as the sisters say, they've done a good job of clearing up their own magical messes so far. Nobody really knows how advanced Wyatt's powers are, or will become. That's why the cleaners appear, to nip things in the bud. The Cleaners didn't want to chance that the sisters could clean Wyatt's magic up, just incase they couldn't. Therefore intervening themselves, just in case.