Charrrmed! - S7-E4
Revealing mistake: When Leo is on top of the bridge meditating; the water shown in the background is not moving. Also, cars on the bridge move, but often change speeds rather dramatically (sometimes moving fast and other times moving incredibly slowly).
Charrrmed! - S7-E4
Continuity mistake: Baby Chris doesn't have a binkie in his mouth, then does, then doesn't. (00:39:23)
Charrrmed! - S7-E4
Visible crew/equipment: When Sheridan gets off the phone and tells Agent Brody that he checks out for now, in the next shot as Brody walks toward Sheridan we can see the T-mark on the floor where he had been standing. (00:24:40)
Charrrmed! - S7-E4
Continuity mistake: When Piper watches Leo sleeping with Wyatt and Chris, the book on Leo's chest disappears and then reappears. (00:38:45 - 00:39:15)
Charrrmed! - S7-E4
Continuity mistake: When Black Jack Cutting's parrot delivers the invitation to Piper and Phoebe, it drops the invitation on the window sill. When Leo goes to pick the letter up, it moves closer to him than it was before (in particular, watch it relative to the parrot's left foot). (00:29:40)
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.