Skype is probably your best bet here. Install skype on a computer in the play room, create a new account, and add your parent's skype account as the only conta

Skype is probably your best bet here. Install skype on a computer in the play room, create a new account, and add your parent's skype account as the only contact on this fresh account. Set skype to auto-login, auto-answer but reject calls from non-contacts - thus only your parents can call but when you they do the cam/mic will immediately turn on. You could install a big monitor, better speakers, etc if you think that would help your son interact better with them. I would consider the privacy issues, however, of having a dedicated always-on setup (rather than 'call in when you like'). Even from your parents, it would be like they are always listening in to what is going on in the house. I considered setting this up for a similar project but I was concerned about doing 'always on'. The best thing about this set up is that it probably will come in well below $5k if you already have a spare computer, etc.