OP, at 2.5 years, be prepared for your DC to test you when you start with the nanny, even if you lay the ground rules. So, you have to be prepared to deal with that. When I work from home, my 2.5 year old DS is ALWAYS trying to get to me. The key is staying in your office or separate space, and being prepared to say "what did [nanny] say you could do?" when your DC comes knocking on the door to appeal nanny's ruling. We always defer to the nanny during the day when she is on. I've even had to make my son repeat the family mantra "who is in charge? [Nanny] is in charge" for him at points, especially if he perceives any difference in approach (wily toddler!). Anyway, you have gotten great advice from the nannies and other MBs on this thread, but I just want to prepare you for your child to test this more than you think - my DS was fine before he hit 2.5, but now he loves to devise ways to get mommy to come out of the office, so I just keep working and ignore the fake meltdowns and rule appeals that he will sometimes lob my way.