This is such a cute video. Mom and Dad set a camera up in these young sisters' room to monitor them and make sure everything was ok. The parents thought they were alone and having a normal nap, but you can see Dad walk in at the end of the video under the assumption that something mischievous is going on.
While this is humorous, it is important to know that nap time is a very important part of a toddler's life.
According to WebMD, nap time is a time for your child to "recharge and reboot or everyone will suffer the consequences." It is also a great period for mom and dad to get some rest and relaxation, which is very much needed for new parents - both to keep them sane and make sure that they're aware enough to care for their baby.